diff --git a/plugins/calendar/lib/calendar_ui.php b/plugins/calendar/lib/calendar_ui.php
index eac0523f..f99c658c 100644
--- a/plugins/calendar/lib/calendar_ui.php
+++ b/plugins/calendar/lib/calendar_ui.php
@@ -1,903 +1,898 @@
 <?php
 /**
  * User Interface class for the Calendar plugin
  *
  * @author Lazlo Westerhof <hello@lazlo.me>
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2010, Lazlo Westerhof <hello@lazlo.me>
  * Copyright (C) 2014, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 
 class calendar_ui
 {
   private $rc;
   private $cal;
   private $ready = false;
   public $screen;
 
   function __construct($cal)
   {
     $this->cal = $cal;
     $this->rc = $cal->rc;
     $this->screen = $this->rc->task == 'calendar' ? ($this->rc->action ? $this->rc->action: 'calendar') : 'other';
   }
     
   /**
    * Calendar UI initialization and requests handlers
    */
   public function init()
   {
     if ($this->ready)  // already done
       return;
       
     // add taskbar button
     $this->cal->add_button(array(
       'command'    => 'calendar',
       'class'      => 'button-calendar',
       'classsel'   => 'button-calendar button-selected',
       'innerclass' => 'button-inner',
       'label'      => 'calendar.calendar',
       'type'       => 'link'
       ), 'taskbar');
     
     // load basic client script
     $this->cal->include_script('calendar_base.js');
     
     $skin_path = $this->cal->local_skin_path();
     $this->cal->include_stylesheet($skin_path . '/calendar.css');
     
     $this->ready = true;
   }
 
   /**
    * Register handler methods for the template engine
    */
   public function init_templates()
   {
     $this->cal->register_handler('plugin.calendar_css', array($this, 'calendar_css'));
     $this->cal->register_handler('plugin.calendar_list', array($this, 'calendar_list'));
     $this->cal->register_handler('plugin.calendar_select', array($this, 'calendar_select'));
     $this->cal->register_handler('plugin.identity_select', array($this, 'identity_select'));
     $this->cal->register_handler('plugin.category_select', array($this, 'category_select'));
     $this->cal->register_handler('plugin.status_select', array($this, 'status_select'));
     $this->cal->register_handler('plugin.freebusy_select', array($this, 'freebusy_select'));
     $this->cal->register_handler('plugin.priority_select', array($this, 'priority_select'));
     $this->cal->register_handler('plugin.sensitivity_select', array($this, 'sensitivity_select'));
     $this->cal->register_handler('plugin.alarm_select', array($this, 'alarm_select'));
     $this->cal->register_handler('plugin.recurrence_form', array($this->cal->lib, 'recurrence_form'));
     $this->cal->register_handler('plugin.attachments_form', array($this, 'attachments_form'));
     $this->cal->register_handler('plugin.attachments_list', array($this, 'attachments_list'));
     $this->cal->register_handler('plugin.filedroparea', array($this, 'file_drop_area'));
     $this->cal->register_handler('plugin.attendees_list', array($this, 'attendees_list'));
     $this->cal->register_handler('plugin.attendees_form', array($this, 'attendees_form'));
     $this->cal->register_handler('plugin.resources_form', array($this, 'resources_form'));
     $this->cal->register_handler('plugin.resources_list', array($this, 'resources_list'));
     $this->cal->register_handler('plugin.resources_searchform', array($this, 'resources_search_form'));
     $this->cal->register_handler('plugin.resource_info', array($this, 'resource_info'));
     $this->cal->register_handler('plugin.resource_calendar', array($this, 'resource_calendar'));
     $this->cal->register_handler('plugin.attendees_freebusy_table', array($this, 'attendees_freebusy_table'));
     $this->cal->register_handler('plugin.edit_attendees_notify', array($this, 'edit_attendees_notify'));
     $this->cal->register_handler('plugin.edit_recurrence_sync', array($this, 'edit_recurrence_sync'));
     $this->cal->register_handler('plugin.edit_recurring_warning', array($this, 'recurring_event_warning'));
     $this->cal->register_handler('plugin.event_rsvp_buttons', array($this, 'event_rsvp_buttons'));
     $this->cal->register_handler('plugin.angenda_options', array($this, 'angenda_options'));
     $this->cal->register_handler('plugin.events_import_form', array($this, 'events_import_form'));
     $this->cal->register_handler('plugin.events_export_form', array($this, 'events_export_form'));
     $this->cal->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
     $this->cal->register_handler('plugin.searchform', array($this->rc->output, 'search_form'));  // use generic method from rcube_template
   }
 
   /**
    * Adds CSS stylesheets to the page header
    */
   public function addCSS()
   {
     $skin_path = $this->cal->local_skin_path();
     $this->cal->include_stylesheet($skin_path . '/fullcalendar.css');
   }
 
   /**
    * Adds JS files to the page header
    */
   public function addJS()
   {
     $this->cal->include_script('calendar_ui.js');
     $this->cal->include_script('lib/js/fullcalendar.js');
     $this->rc->output->include_script('treelist.js');
-
-    // include kolab folderlist widget if available
-    if (in_array('libkolab', $this->cal->api->loaded_plugins())) {
-        $this->cal->api->include_script('libkolab/js/folderlist.js');
-        $this->cal->api->include_script('libkolab/js/audittrail.js');
-    }
+    $this->cal->api->include_script('libkolab/libkolab.js');
 
     jqueryui::miniColors();
   }
 
   /**
    *
    */
   function calendar_css($attrib = array())
   {
     $mode = $this->rc->config->get('calendar_event_coloring', $this->cal->defaults['calendar_event_coloring']);
     $categories = $this->cal->driver->list_categories();
     $css = "\n";
     
     foreach ((array)$categories as $class => $color) {
       if (empty($color))
         continue;
       
       $class = 'cat-' . asciiwords(strtolower($class), true);
       $css  .= ".$class { color: #$color }\n";
       if ($mode > 0) {
         if ($mode == 2) {
           $css .= ".fc-event-$class .fc-event-bg {";
           $css .= " opacity: 0.9;";
           $css .= " filter: alpha(opacity=90);";
         }
         else {
           $css .= ".fc-event-$class.fc-event-skin, ";
           $css .= ".fc-event-$class .fc-event-skin, ";
           $css .= ".fc-event-$class .fc-event-inner {";
         }
         $css .= " background-color: #" . $color . ";";
         if ($mode % 2)
           $css .= " border-color: #$color;";
         $css .= "}\n";
       }
     }
     
     $calendars = $this->cal->driver->list_calendars();
     foreach ((array)$calendars as $id => $prop) {
       if (!$prop['color'])
         continue;
       $css .= $this->calendar_css_classes($id, $prop, $mode, $attrib);
     }
     
     return html::tag('style', array('type' => 'text/css'), $css);
   }
 
   /**
    *
    */
   public function calendar_css_classes($id, $prop, $mode, $attrib)
   {
     $color = $folder_color = $prop['color'];
 
     // replace white with skin-defined color
     if (!empty($attrib['folder-fallback-color']) && preg_match('/^f+$/i', $folder_color)) {
         $folder_color = $attrib['folder-fallback-color'];
     }
 
     $class = 'cal-' . asciiwords($id, true);
     $css   = str_replace('$class', $class, $attrib['folder-class']) ?: "li .$class";
     $css  .= ", #eventshow .$class { color: #$folder_color; }\n";
 
     if ($mode != 1) {
       if ($mode == 3) {
         $css .= ".fc-event-$class .fc-event-bg {";
         $css .= " opacity: 0.9;";
         $css .= " filter: alpha(opacity=90);";
       }
       else {
         $css .= ".fc-event-$class, ";
         $css .= ".fc-event-$class .fc-event-inner {";
       }
       if (!$prop['printmode'])
         $css .= " background-color: #$color;";
       if ($mode % 2 == 0)
       $css .= " border-color: #$color;";
       $css .= "}\n";
     }
 
     return $css . ".$class .handle { background-color: #$color; }\n";
   }
 
   /**
    *
    */
   function calendar_list($attrib = array())
   {
     $html = '';
     $jsenv = array();
     $tree = true;
     $calendars = $this->cal->driver->list_calendars(0, $tree);
 
     // walk folder tree
     if (is_object($tree)) {
       $html = $this->list_tree_html($tree, $calendars, $jsenv, $attrib);
 
       // append birthdays calendar which isn't part of $tree
       if ($bdaycal = $calendars[calendar_driver::BIRTHDAY_CALENDAR_ID]) {
         $calendars = array(calendar_driver::BIRTHDAY_CALENDAR_ID => $bdaycal);
       }
       else {
         $calendars = array();  // clear array for flat listing
       }
     }
     else {
       // fall-back to flat folder listing
       $attrib['class'] .= ' flat';
     }
 
     foreach ((array)$calendars as $id => $prop) {
       if ($attrib['activeonly'] && !$prop['active'])
         continue;
 
       $html .= html::tag('li', array('id' => 'rcmlical' . $id, 'class' => $prop['group']),
         $content = $this->calendar_list_item($id, $prop, $jsenv, $attrib['activeonly'])
       );
     }
 
     $this->rc->output->set_env('source', rcube_utils::get_input_value('source', rcube_utils::INPUT_GET));
     $this->rc->output->set_env('calendars', $jsenv);
     $this->rc->output->add_gui_object('calendarslist', $attrib['id']);
 
     return html::tag('ul', $attrib, $html, html::$common_attrib);
   }
 
   /**
    * Return html for a structured list <ul> for the folder tree
    */
   public function list_tree_html($node, $data, &$jsenv, $attrib)
   {
     $out = '';
     foreach ($node->children as $folder) {
       $id = $folder->id;
       $prop = $data[$id];
       $is_collapsed = false; // TODO: determine this somehow?
 
       $content = $this->calendar_list_item($id, $prop, $jsenv, $attrib['activeonly']);
 
       if (!empty($folder->children)) {
         $content .= html::tag('ul', array('style' => ($is_collapsed ? "display:none;" : null)),
           $this->list_tree_html($folder, $data, $jsenv, $attrib));
       }
 
       if (strlen($content)) {
         $out .= html::tag('li', array(
             'id' => 'rcmlical' . rcube_utils::html_identifier($id),
             'class' => $prop['group'] . ($prop['virtual'] ? ' virtual' : ''),
           ),
           $content);
       }
     }
 
     return $out;
   }
 
   /**
    * Helper method to build a calendar list item (HTML content and js data)
    */
   public function calendar_list_item($id, $prop, &$jsenv, $activeonly = false)
   {
     // enrich calendar properties with settings from the driver
     if (!$prop['virtual']) {
       unset($prop['user_id']);
       $prop['alarms']      = $this->cal->driver->alarms;
       $prop['attendees']   = $this->cal->driver->attendees;
       $prop['freebusy']    = $this->cal->driver->freebusy;
       $prop['attachments'] = $this->cal->driver->attachments;
       $prop['undelete']    = $this->cal->driver->undelete;
       $prop['feedurl']     = $this->cal->get_url(array('_cal' => $this->cal->ical_feed_hash($id) . '.ics', 'action' => 'feed'));
 
       $jsenv[$id] = $prop;
     }
 
     $classes = array('calendar', 'cal-'  . asciiwords($id, true));
     $title = $prop['title'] ?: ($prop['name'] != $prop['listname'] || strlen($prop['name']) > 25 ?
       html_entity_decode($prop['name'], ENT_COMPAT, RCUBE_CHARSET) : '');
 
     if ($prop['virtual'])
       $classes[] = 'virtual';
     else if (!$prop['editable'])
       $classes[] = 'readonly';
     if ($prop['subscribed'])
       $classes[] = 'subscribed';
     if ($prop['subscribed'] === 2)
       $classes[] = 'partial';
     if ($prop['class'])
       $classes[] = $prop['class'];
 
     $content = '';
     if (!$activeonly || $prop['active']) {
       $label_id = 'cl:' . $id;
       $content = html::div(join(' ', $classes),
         html::a(array('class' => 'calname', 'id' => $label_id, 'title' => $title, 'href' => '#'), rcube::Q($prop['editname'] ?: $prop['listname']))
         . ($prop['virtual'] ? '' :
           html::tag('input', array('type' => 'checkbox', 'name' => '_cal[]', 'value' => $id, 'checked' => $prop['active'], 'aria-labelledby' => $label_id), '') .
           html::span('actions', 
             ($prop['removable'] ? html::a(array('href' => '#', 'class' => 'remove', 'title' => $this->cal->gettext('removelist')), ' ') : '') .
             html::a(array('href' => '#', 'class' => 'quickview', 'title' => $this->cal->gettext('quickview'), 'role' => 'checkbox', 'aria-checked' => 'false'), '') .
             (isset($prop['subscribed']) ? html::a(array('href' => '#', 'class' => 'subscribed', 'title' => $this->cal->gettext('calendarsubscribe'), 'role' => 'checkbox', 'aria-checked' => $prop['subscribed'] ? 'true' : 'false'), ' ') : '')
           ) .
           html::span(array('class' => 'handle', 'style' => "background-color: #" . ($prop['color'] ?: 'f00')), '&nbsp;')
         )
       );
     }
 
     return $content;
   }
 
   /**
    *
    */
   function angenda_options($attrib = array())
   {
     $attrib += array('id' => 'agendaoptions');
     $attrib['style'] .= 'display:none';
     
     $select_range = new html_select(array('name' => 'listrange', 'id' => 'agenda-listrange', 'class' => 'form-control'));
     $select_range->add(1 . ' ' . preg_replace('/\(.+\)/', '', $this->cal->lib->gettext('days')), $days);
     foreach (array(2,5,7,14,30,60,90,180,365) as $days)
       $select_range->add($days . ' ' . preg_replace('/\(|\)/', '', $this->cal->lib->gettext('days')), $days);
     
     $html .= html::label('agenda-listrange', $this->cal->gettext('listrange'));
     $html .= $select_range->show($this->rc->config->get('calendar_agenda_range', $this->cal->defaults['calendar_agenda_range']));
     
     $select_sections = new html_select(array('name' => 'listsections', 'id' => 'agenda-listsections', 'class' => 'form-control'));
     $select_sections->add('---', '');
     foreach (array('day' => 'libcalendaring.days', 'week' => 'libcalendaring.weeks', 'month' => 'libcalendaring.months', 'smart' => 'calendar.smartsections') as $val => $label)
       $select_sections->add(preg_replace('/\(|\)/', '', ucfirst($this->rc->gettext($label))), $val);
     
     $html .= html::span('spacer', '&nbsp;');
     $html .= html::label('agenda-listsections', $this->cal->gettext('listsections'));
     $html .= $select_sections->show($this->rc->config->get('calendar_agenda_sections', $this->cal->defaults['calendar_agenda_sections']));
     
     return html::div($attrib, $html);
   }
 
   /**
    * Render a HTML select box for calendar selection
    */
   function calendar_select($attrib = array())
   {
     $attrib['name']       = 'calendar';
     $attrib['is_escaped'] = true;
     $select = new html_select($attrib);
 
     foreach ((array)$this->cal->driver->list_calendars() as $id => $prop) {
       if ($prop['editable'] || strpos($prop['rights'], 'i') !== false)
         $select->add($prop['name'], $id);
     }
 
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box for user identity selection
    */
   function identity_select($attrib = array())
   {
     $attrib['name'] = 'identity';
     $select         = new html_select($attrib);
     $identities     = $this->rc->user->list_emails();
 
     foreach ($identities as $ident) {
         $select->add(format_email_recipient($ident['email'], $ident['name']), $ident['identity_id']);
     }
 
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box to select an event category
    */
   function category_select($attrib = array())
   {
     $attrib['name'] = 'categories';
     $select = new html_select($attrib);
     $select->add('---', '');
     foreach (array_keys((array)$this->cal->driver->list_categories()) as $cat) {
       $select->add($cat, $cat);
     }
 
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box for status property
    */
   function status_select($attrib = array())
   {
     $attrib['name'] = 'status';
     $select = new html_select($attrib);
     $select->add('---', '');
     $select->add($this->cal->gettext('status-confirmed'), 'CONFIRMED');
     $select->add($this->cal->gettext('status-cancelled'), 'CANCELLED');
     $select->add($this->cal->gettext('status-tentative'), 'TENTATIVE');
     return $select->show(null);
   }
 
   /**
    * Render a HTML select box for free/busy/out-of-office property
    */
   function freebusy_select($attrib = array())
   {
     $attrib['name'] = 'freebusy';
     $select = new html_select($attrib);
     $select->add($this->cal->gettext('free'), 'free');
     $select->add($this->cal->gettext('busy'), 'busy');
     // out-of-office is not supported by libkolabxml (#3220)
     // $select->add($this->cal->gettext('outofoffice'), 'outofoffice');
     $select->add($this->cal->gettext('tentative'), 'tentative');
     return $select->show(null);
   }
 
   /**
    * Render a HTML select for event priorities
    */
   function priority_select($attrib = array())
   {
     $attrib['name'] = 'priority';
     $select = new html_select($attrib);
     $select->add('---', '0');
     $select->add('1 '.$this->cal->gettext('highest'), '1');
     $select->add('2 '.$this->cal->gettext('high'),    '2');
     $select->add('3 ',                                '3');
     $select->add('4 ',                                '4');
     $select->add('5 '.$this->cal->gettext('normal'),  '5');
     $select->add('6 ',                                '6');
     $select->add('7 ',                                '7');
     $select->add('8 '.$this->cal->gettext('low'),     '8');
     $select->add('9 '.$this->cal->gettext('lowest'),  '9');
     return $select->show(null);
   }
   
   /**
    * Render HTML input for sensitivity selection
    */
   function sensitivity_select($attrib = array())
   {
     $attrib['name'] = 'sensitivity';
     $select = new html_select($attrib);
     $select->add($this->cal->gettext('public'), 'public');
     $select->add($this->cal->gettext('private'), 'private');
     $select->add($this->cal->gettext('confidential'), 'confidential');
     return $select->show(null);
   }
   
   /**
    * Render HTML form for alarm configuration
    */
   function alarm_select($attrib = array())
   {
     return $this->cal->lib->alarm_select($attrib, $this->cal->driver->alarm_types, $this->cal->driver->alarm_absolute);
   }
 
   /**
    * Render HTML for attendee notification warning
    */
   function edit_attendees_notify($attrib = array())
   {
     $checkbox = new html_checkbox(array('name' => '_notify', 'id' => 'edit-attendees-donotify', 'value' => 1));
     return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->cal->gettext('sendnotifications')));
   }
 
   /**
    * Render HTML for recurrence option to align start date with the recurrence rule
    */
   function edit_recurrence_sync($attrib = array())
   {
     $checkbox = new html_checkbox(array('name' => '_start_sync', 'value' => 1));
     return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->cal->gettext('eventstartsync')));
   }
 
   /**
    * Generate the form for recurrence settings
    */
   function recurring_event_warning($attrib = array())
   {
     $attrib['id'] = 'edit-recurring-warning';
     
     $radio = new html_radiobutton(array('name' => '_savemode', 'class' => 'edit-recurring-savemode'));
     $form = html::label(null, $radio->show('', array('value' => 'current')) . $this->cal->gettext('currentevent')) . ' ' .
        html::label(null, $radio->show('', array('value' => 'future')) . $this->cal->gettext('futurevents')) . ' ' .
        html::label(null, $radio->show('all', array('value' => 'all')) . $this->cal->gettext('allevents')) . ' ' .
        html::label(null, $radio->show('', array('value' => 'new')) . $this->cal->gettext('saveasnew'));
        
     return html::div($attrib, html::div('message', html::span('ui-icon ui-icon-alert', '') . $this->cal->gettext('changerecurringeventwarning')) . html::div('savemode', $form));
   }
 
   /**
    * Form for uploading and importing events
    */
   function events_import_form($attrib = array())
   {
     if (!$attrib['id'])
       $attrib['id'] = 'rcmImportForm';
 
     // Get max filesize, enable upload progress bar
     $max_filesize = $this->rc->upload_init();
 
     $accept = '.ics, text/calendar, text/x-vcalendar, application/ics';
     if (class_exists('ZipArchive', false)) {
       $accept .= ', .zip, application/zip';
     }
 
     $input = new html_inputfield(array(
       'type' => 'file', 'name' => '_data', 'size' => $attrib['uploadfieldsize'],
       'accept' => $accept));
 
     $select = new html_select(array('name' => '_range', 'id' => 'event-import-range'));
     $select->add(array(
         $this->cal->gettext('onemonthback'),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>2))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>3))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>6))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>12))),
         $this->cal->gettext('all'),
       ),
       array('1','2','3','6','12',0));
 
     $html .= html::div('form-section',
       html::div(null, $input->show()) .
       html::div('hint', $this->rc->gettext(array('name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize))))
     );
 
     $html .= html::div('form-section',
       html::label('event-import-calendar', $this->cal->gettext('calendar')) .
       $this->calendar_select(array('name' => 'calendar', 'id' => 'event-import-calendar'))
     );
 
     $html .= html::div('form-section',
       html::label('event-import-range', $this->cal->gettext('importrange')) .
       $select->show(1)
     );
 
     $this->rc->output->add_gui_object('importform', $attrib['id']);
     $this->rc->output->add_label('import');
 
     return html::tag('form', array('action' => $this->rc->url(array('task' => 'calendar', 'action' => 'import_events')),
       'method' => "post", 'enctype' => 'multipart/form-data', 'id' => $attrib['id']),
       $html
     );
   }
 
   /**
    * Form to select options for exporting events
    */
   function events_export_form($attrib = array())
   {
     if (!$attrib['id'])
       $attrib['id'] = 'rcmExportForm';
 
     $html = html::div('form-section form-group row',
       html::label(array('for' => 'event-export-calendar', 'class' => 'col-sm-4 col-form-label'), $this->cal->gettext('calendar'))
         . html::div('col-sm-8', $this->calendar_select(array('name' => 'calendar', 'id' => 'event-export-calendar', 'class' => 'form-control'))));
 
     $select = new html_select(array('name' => 'range', 'id' => 'event-export-range', 'class' => 'form-control'));
     $select->add(array(
         $this->cal->gettext('all'),
         $this->cal->gettext('onemonthback'),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>2))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>3))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>6))),
         $this->cal->gettext(array('name' => 'nmonthsback', 'vars' => array('nr'=>12))),
         $this->cal->gettext('customdate'),
       ),
       array(0,'1','2','3','6','12','custom'));
 
     $startdate = new html_inputfield(array('name' => 'start', 'size' => 11, 'id' => 'event-export-startdate'));
 
     $html .= html::div('form-section form-group row',
       html::label(array('for' => 'event-export-range', 'class' => 'col-sm-4 col-form-label'), $this->cal->gettext('exportrange'))
         . html::div('col-sm-8', $select->show(0) . html::span(array('style'=>'display:none'), $startdate->show())));
 
     $checkbox = new html_checkbox(array('name' => 'attachments', 'id' => 'event-export-attachments', 'value' => 1));
     $html .= html::div('form-section form-group row',
       html::label(array('for' => 'event-export-attachments', 'class' => 'col-sm-4 col-form-label'), $this->cal->gettext('exportattachments'))
         . html::div('col-sm-8', $checkbox->show(1)));
 
     $this->rc->output->add_gui_object('exportform', $attrib['id']);
 
     return html::tag('form', $attrib + array(
         'action' => $this->rc->url(array('task' => 'calendar', 'action' => 'export_events')),
         'method' => "post",
         'id' => $attrib['id']
       ),
       $html
     );
   }
 
   /**
    * Generate the form for event attachments upload
    */
   function attachments_form($attrib = array())
   {
     // add ID if not given
     if (!$attrib['id']) {
       $attrib['id'] = 'rcmUploadForm';
     }
 
     return $this->rc->upload_form($attrib, 'uploadform', 'upload-file', array('multiple' => true));
   }
 
   /**
    * Register UI object for HTML5 drag & drop file upload
    */
   function file_drop_area($attrib = array())
   {
       if ($attrib['id']) {
           $this->rc->output->add_gui_object('filedrop', $attrib['id']);
           $this->rc->output->set_env('filedrop', array('action' => 'upload', 'fieldname' => '_attachments'));
       }
   }
 
   /**
    * Generate HTML element for attachments list
    */
   function attachments_list($attrib = array())
   {
     if (!$attrib['id'])
       $attrib['id'] = 'rcmAttachmentList';
 
     $skin_path = $this->cal->local_skin_path();
     if ($attrib['deleteicon']) {
       $_SESSION[calendar::SESSION_KEY . '_deleteicon'] = $skin_path . $attrib['deleteicon'];
       $this->rc->output->set_env('deleteicon', $skin_path . $attrib['deleteicon']);
     }
     if ($attrib['cancelicon'])
       $this->rc->output->set_env('cancelicon', $skin_path . $attrib['cancelicon']);
     if ($attrib['loadingicon'])
       $this->rc->output->set_env('loadingicon', $skin_path . $attrib['loadingicon']);
 
     $this->rc->output->add_gui_object('attachmentlist', $attrib['id']);
     $this->attachmentlist_id = $attrib['id'];
 
     return html::tag('ul', $attrib, '', html::$common_attrib);
   }
 
   /**
    * Handler for calendar form template.
    * The form content could be overriden by the driver
    */
   function calendar_editform($action, $calendar = array())
   {
     $this->action   = $action;
     $this->calendar = $calendar;
 
     // load miniColors js/css files
     jqueryui::miniColors();
 
     $this->rc->output->add_handler('calendarform', array($this, 'calendarform'));
     $this->rc->output->send('calendar.folderform');
   }
 
   /**
    * Handler for calendar form template.
    * The form content could be overriden by the driver
    */
   function calendarform($attrib)
   {
     // compose default calendar form fields
     $input_name  = new html_inputfield(array('name' => 'name', 'id' => 'calendar-name', 'size' => 20));
     $input_color = new html_inputfield(array('name' => 'color', 'id' => 'calendar-color', 'size' => 7, 'class' => 'colors'));
 
     $formfields = array(
       'name' => array(
         'label' => $this->cal->gettext('name'),
         'value' => $input_name->show($calendar['name']),
         'id'    => 'calendar-name',
       ),
       'color' => array(
         'label' => $this->cal->gettext('color'),
         'value' => $input_color->show($calendar['color']),
         'id'    => 'calendar-color',
       ),
     );
 
     if ($this->cal->driver->alarms) {
       $checkbox = new html_checkbox(array('name' => 'showalarms', 'id' => 'calendar-showalarms', 'value' => 1));
       $formfields['showalarms'] = array(
         'label' => $this->cal->gettext('showalarms'),
         'value' => $checkbox->show($this->calendar['showalarms'] ? 1 :0),
         'id'    => 'calendar-showalarms',
       );
     }
 
     // allow driver to extend or replace the form content
     return html::tag('form', $attrib + array('action' => "#", 'method' => "get", 'id' => 'calendarpropform'),
       $this->cal->driver->calendar_form($this->action, $this->calendar, $formfields)
     );
   }
 
   /**
    *
    */
   function attendees_list($attrib = array())
   {
     // add "noreply" checkbox to attendees table only
     $invitations = strpos($attrib['id'], 'attend') !== false;
 
     $invite = new html_checkbox(array('value' => 1, 'id' => 'edit-attendees-invite'));
     $table  = new html_table(array('cols' => 5 + intval($invitations), 'border' => 0, 'cellpadding' => 0, 'class' => 'rectable'));
 
     $table->add_header('role', $this->cal->gettext('role'));
     $table->add_header('name', $this->cal->gettext($attrib['coltitle'] ?: 'attendee'));
     $table->add_header('availability', $this->cal->gettext('availability'));
     $table->add_header('confirmstate', $this->cal->gettext('confirmstate'));
     if ($invitations) {
       $table->add_header(array('class' => 'invite', 'title' => $this->cal->gettext('sendinvitations')),
         $invite->show(1) . html::label('edit-attendees-invite', $this->cal->gettext('sendinvitations')));
     }
     $table->add_header('options', '');
 
     // hide invite column if disabled by config
     $itip_notify = (int)$this->rc->config->get('calendar_itip_send_option', $this->cal->defaults['calendar_itip_send_option']);
     if ($invitations && !($itip_notify & 2)) {
         $css = sprintf('#%s td.invite, #%s th.invite { display:none !important }', $attrib['id'], $attrib['id']);
         $this->rc->output->add_footer(html::tag('style', array('type' => 'text/css'), $css));
     }
 
     return $table->show($attrib);
   }
 
   /**
    *
    */
   function attendees_form($attrib = array())
   {
     $input    = new html_inputfield(array('name' => 'participant', 'id' => 'edit-attendee-name', 'class' => 'form-control'));
     $textarea = new html_textarea(array('name' => 'comment', 'id' => 'edit-attendees-comment', 'class' => 'form-control',
         'rows' => 4, 'cols' => 55, 'title' => $this->cal->gettext('itipcommenttitle')));
 
     return html::div($attrib,
       html::div('form-searchbar', $input->show() . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-add', 'value' => $this->cal->gettext('addattendee'))) . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-schedule', 'value' => $this->cal->gettext('scheduletime').'...'))) .
       html::p('attendees-commentbox', html::label(null, $this->cal->gettext('itipcomment') . $textarea->show()))
     );
   }
 
   /**
    *
    */
   function resources_form($attrib = array())
   {
     $input = new html_inputfield(array('name' => 'resource', 'id' => 'edit-resource-name', 'class' => 'form-control'));
 
     return html::div($attrib,
       html::div('form-searchbar', $input->show() . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-resource-add', 'value' => $this->cal->gettext('addresource'))) . " " .
         html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-resource-find', 'value' => $this->cal->gettext('findresources').'...')))
       );
   }
 
   /**
    *
    */
   function resources_list($attrib = array())
   {
     $attrib += array('id' => 'calendar-resources-list');
 
     $this->rc->output->add_gui_object('resourceslist', $attrib['id']);
 
     return html::tag('ul', $attrib, '', html::$common_attrib);
   }
 
   /**
    *
    */
   public function resource_info($attrib = array())
   {
     $attrib += array('id' => 'calendar-resources-info');
 
     $this->rc->output->add_gui_object('resourceinfo', $attrib['id']);
     $this->rc->output->add_gui_object('resourceownerinfo', $attrib['id'] . '-owner');
 
     // copy address book labels for owner details to client
     $this->rc->output->add_label('name','firstname','surname','department','jobtitle','email','phone','address');
 
     $table_attrib = array('id','class','style','width','summary','cellpadding','cellspacing','border');
 
     return html::tag('table', $attrib,
         html::tag('tbody', null, ''), $table_attrib) .
 
       html::tag('table', array('id' => $attrib['id'] . '-owner', 'style' => 'display:none') + $attrib,
         html::tag('thead', null,
           html::tag('tr', null,
             html::tag('td', array('colspan' => 2), rcube::Q($this->cal->gettext('resourceowner')))
           )
         ) .
         html::tag('tbody', null, ''),
         $table_attrib);
   }
 
   /**
    *
    */
   public function resource_calendar($attrib = array())
   {
     $attrib += array('id' => 'calendar-resources-calendar');
 
     $this->rc->output->add_gui_object('resourceinfocalendar', $attrib['id']);
 
     return html::div($attrib, '');
   }
 
   /**
    * GUI object 'searchform' for the resource finder dialog
    *
    * @param array Named parameters
    * @return string HTML code for the gui object
    */
   function resources_search_form($attrib)
   {
     $attrib += array('command' => 'search-resource', 'id' => 'rcmcalresqsearchbox', 'autocomplete' => 'off');
     $attrib['name'] = '_q';
 
     $input_q = new html_inputfield($attrib);
     $out = $input_q->show();
 
     // add form tag around text field
     $out = $this->rc->output->form_tag(array(
       'name' => "rcmcalresoursqsearchform",
       'onsubmit' => rcmail_output::JS_OBJECT_NAME . ".command('" . $attrib['command'] . "'); return false",
       'style' => "display:inline"),
       $out);
 
     return $out;
   }
 
   /**
    *
    */
   function attendees_freebusy_table($attrib = array())
   {
     $table = new html_table(array('cols' => 2, 'border' => 0, 'cellspacing' => 0));
     $table->add('attendees',
       html::tag('h3', 'boxtitle', $this->cal->gettext('tabattendees')) .
       html::div('timesheader', '&nbsp;') .
       html::div(array('id' => 'schedule-attendees-list', 'class' => 'attendees-list'), '')
     );
     $table->add('times',
       html::div('scroll',
         html::tag('table', array('id' => 'schedule-freebusy-times', 'border' => 0, 'cellspacing' => 0), html::tag('thead') . html::tag('tbody')) .
         html::div(array('id' => 'schedule-event-time', 'style' => 'display:none'), '&nbsp;')
       )
     );
     
     return $table->show($attrib);
   }
 
   /**
    *
    */
   function event_invitebox($attrib = array())
   {
     if ($this->cal->event) {
       return html::div($attrib,
         $this->cal->itip->itip_object_details_table($this->cal->event, $this->cal->itip->gettext('itipinvitation')) .
         $this->cal->invitestatus
       );
     }
     
     return '';
   }
 
   function event_rsvp_buttons($attrib = array())
   {
     $actions = array('accepted','tentative','declined');
     if ($attrib['delegate'] !== 'false')
       $actions[] = 'delegated';
 
     return $this->cal->itip->itip_rsvp_buttons($attrib, $actions);
   }
 
 }
diff --git a/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php b/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
index 726b66cf..a9f6aad5 100644
--- a/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
+++ b/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
@@ -1,363 +1,363 @@
 <?php
 
 /**
  * Kolab address book UI
  *
  * @author Aleksander Machniak <machniak@kolabsys.com>
  *
  * Copyright (C) 2012, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 class kolab_addressbook_ui
 {
     private $plugin;
     private $rc;
 
     /**
      * Class constructor
      *
      * @param kolab_addressbook $plugin Plugin object
      */
     public function __construct($plugin)
     {
         $this->rc     = rcube::get_instance();
         $this->plugin = $plugin;
 
         $this->init_ui();
     }
 
     /**
      * Adds folders management functionality to Addressbook UI
      */
     private function init_ui()
     {
         if (!empty($this->rc->action) && !preg_match('/^plugin\.book/', $this->rc->action) && $this->rc->action != 'show') {
             return;
         }
 
         // Include script
         $this->plugin->include_script('kolab_addressbook.js');
 
         if (empty($this->rc->action)) {
             // Include stylesheet (for directorylist)
             $this->plugin->include_stylesheet($this->plugin->local_skin_path().'/kolab_addressbook.css');
 
             // include kolab folderlist widget if available
             if (in_array('libkolab', $this->plugin->api->loaded_plugins())) {
                 $this->plugin->api->include_script('libkolab/js/folderlist.js');
             }
 
             $this->rc->output->add_footer($this->rc->output->parse('kolab_addressbook.search_addon', false, false));
 
             // Add actions on address books
             $options = array('book-create', 'book-edit', 'book-delete', 'book-remove');
             $idx     = 0;
 
             if ($dav_url = $this->rc->config->get('kolab_addressbook_carddav_url')) {
               $options[] = 'book-showurl';
               $this->rc->output->set_env('kolab_addressbook_carddav_url', true);
 
               // set CardDAV URI for specified ldap addressbook
               if ($ldap_abook = $this->rc->config->get('kolab_addressbook_carddav_ldap')) {
                 $dav_ldap_url = strtr($dav_url, array(
                     '%h' => $_SERVER['HTTP_HOST'],
                     '%u' => urlencode($this->rc->get_user_name()),
                     '%i' => 'ldap-directory',
                     '%n' => '',
                 ));
                 $this->rc->output->set_env('kolab_addressbook_carddav_ldap', $ldap_abook);
                 $this->rc->output->set_env('kolab_addressbook_carddav_ldap_url', $dav_ldap_url);
               }
             }
 
             foreach ($options as $command) {
                 $content = html::tag('li', $idx ? null : array('class' => 'separator_above'),
                     $this->plugin->api->output->button(array(
                         'label'    => 'kolab_addressbook.'.str_replace('-', '', $command),
                         'domain'   => $this->ID,
                         'class'    => str_replace('-', ' ', $command) . ' disabled',
                         'classact' => str_replace('-', ' ', $command) . ' active',
                         'command'  => $command,
                         'type'     => 'link'
                 )));
                 $this->plugin->api->add_content($content, 'groupoptions');
                 $idx++;
             }
 
             // Link to Settings/Folders
             $content = html::tag('li', array('class' => 'separator_above'),
                 $this->plugin->api->output->button(array(
                     'label'    => 'managefolders',
                     'type'     => 'link',
                     'class'    => 'folders disabled',
                     'classact' => 'folders active',
                     'command'  => 'folders',
                     'task'     => 'settings',
             )));
             $this->plugin->api->add_content($content, 'groupoptions');
 
             $this->rc->output->add_label('kolab_addressbook.bookdeleteconfirm',
                 'kolab_addressbook.bookdeleting', 'kolab_addressbook.bookshowurl',
                 'kolab_addressbook.carddavurldescription',
                 'kolab_addressbook.bookedit',
                 'kolab_addressbook.bookdelete',
                 'kolab_addressbook.bookshowurl',
                 'kolab_addressbook.findaddressbooks',
                 'kolab_addressbook.searchterms',
                 'kolab_addressbook.foldersearchform',
                 'kolab_addressbook.listsearchresults',
                 'kolab_addressbook.nraddressbooksfound',
                 'kolab_addressbook.noaddressbooksfound',
                 'kolab_addressbook.foldersubscribe',
                 'resetsearch'
             );
 
             if ($this->plugin->bonnie_api) {
                 $this->rc->output->set_env('kolab_audit_trail', true);
-                $this->plugin->api->include_script('libkolab/js/audittrail.js');
+                $this->plugin->api->include_script('libkolab/libkolab.js');
 
                 $this->rc->output->add_label(
                     'kolab_addressbook.showhistory',
                     'kolab_addressbook.objectchangelog',
                     'kolab_addressbook.objectdiff',
                     'kolab_addressbook.objectdiffnotavailable',
                     'kolab_addressbook.objectchangelognotavailable',
                     'kolab_addressbook.revisionrestoreconfirm'
                 );
 
                 $this->plugin->add_hook('render_page', array($this, 'render_audittrail_page'));
                 $this->plugin->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
             }
         }
         // include stylesheet for audit trail
         else if ($this->rc->action == 'show' && $this->plugin->bonnie_api) {
             $this->plugin->include_stylesheet($this->plugin->local_skin_path().'/kolab_addressbook.css', true);
             $this->rc->output->add_label('kolab_addressbook.showhistory');
         }
         // book create/edit form
         else {
             $this->rc->output->add_label('kolab_addressbook.nobooknamewarning',
                 'kolab_addressbook.booksaving');
         }
     }
 
 
     /**
      * Handler for address book create/edit action
      */
     public function book_edit()
     {
         $this->rc->output->add_handler('bookdetails', array($this, 'book_form'));
         $this->rc->output->send('kolab_addressbook.bookedit');
     }
 
 
     /**
      * Handler for 'bookdetails' object returning form content for book create/edit
      *
      * @param array $attr Object attributes
      *
      * @return string HTML output
      */
     public function book_form($attrib)
     {
         $action = trim(rcube_utils::get_input_value('_act', rcube_utils::INPUT_GPC));
         $folder = trim(rcube_utils::get_input_value('_source', rcube_utils::INPUT_GPC, true)); // UTF8
 
         $hidden_fields[] = array('name' => '_source', 'value' => $folder);
 
         $folder  = rcube_charset::convert($folder, RCUBE_CHARSET, 'UTF7-IMAP');
         $storage = $this->rc->get_storage();
         $delim   = $storage->get_hierarchy_delimiter();
 
         if ($this->rc->action == 'plugin.book-save') {
             // save error
             $name      = trim(rcube_utils::get_input_value('_name', rcube_utils::INPUT_GPC, true)); // UTF8
             $old       = trim(rcube_utils::get_input_value('_oldname', rcube_utils::INPUT_GPC, true)); // UTF7-IMAP
             $path_imap = trim(rcube_utils::get_input_value('_parent', rcube_utils::INPUT_GPC, true)); // UTF7-IMAP
 
             $hidden_fields[] = array('name' => '_oldname', 'value' => $old);
 
             $folder = $old;
         }
         else if ($action == 'edit') {
             $path_imap = explode($delim, $folder);
             $name      = rcube_charset::convert(array_pop($path_imap), 'UTF7-IMAP');
             $path_imap = implode($path_imap, $delim);
         }
         else { // create
             $path_imap = $folder;
             $name      = '';
             $folder    = '';
         }
 
         // Store old name, get folder options
         if (strlen($folder)) {
             $hidden_fields[] = array('name' => '_oldname', 'value' => $folder);
 
             $options = $storage->folder_info($folder);
         }
 
         $form = array();
 
         // General tab
         $form['props'] = array(
             'name' => $this->rc->gettext('properties'),
         );
 
         if (!empty($options) && ($options['norename'] || $options['protected'])) {
             $foldername = rcube::Q(str_replace($delim, ' &raquo; ', kolab_storage::object_name($folder)));
         }
         else {
             $foldername = new html_inputfield(array('name' => '_name', 'id' => '_name', 'size' => 30));
             $foldername = $foldername->show($name);
         }
 
         $form['props']['fieldsets']['location'] = array(
             'name'  => $this->rc->gettext('location'),
             'content' => array(
                 'name' => array(
                     'label' => $this->plugin->gettext('bookname'),
                     'value' => $foldername,
                 ),
             ),
         );
 
         if (!empty($options) && ($options['norename'] || $options['protected'])) {
             // prevent user from moving folder
             $hidden_fields[] = array('name' => '_parent', 'value' => $path_imap);
         }
         else {
             $prop   = array('name' => '_parent', 'id' => '_parent');
             $select = kolab_storage::folder_selector('contact', $prop, $folder);
 
             $form['props']['fieldsets']['location']['content']['parent'] = array(
                 'label' => $this->plugin->gettext('parentbook'),
                 'value' => $select->show(strlen($folder) ? $path_imap : ''),
             );
         }
 
         // Allow plugins to modify address book form content (e.g. with ACL form)
         $plugin = $this->rc->plugins->exec_hook('addressbook_form',
             array('form' => $form, 'options' => $options, 'name' => $folder));
 
         $form = $plugin['form'];
 
         // Set form tags and hidden fields
         list($form_start, $form_end) = $this->get_form_tags($attrib, 'plugin.book-save', null, $hidden_fields);
 
         unset($attrib['form']);
 
         // return the complete edit form as table
         $out = "$form_start\n";
 
         // Create form output
         foreach ($form as $idx => $tab) {
             if (!empty($tab['fieldsets']) && is_array($tab['fieldsets'])) {
                 $content = '';
                 foreach ($tab['fieldsets'] as $fieldset) {
                     $subcontent = $this->get_form_part($fieldset);
                     if ($subcontent) {
                         $content .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($fieldset['name'])) . $subcontent) ."\n";
                     }
                 }
             }
             else {
                 $content = $this->get_form_part($tab);
             }
 
             if ($content) {
                 if ($idx != 'props') {
                     $out .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($tab['name'])) . $content) ."\n";
                 }
                 else {
                     $out .= $content ."\n";
                 }
             }
         }
 
         $out .= "\n$form_end";
 
         return $out;
     }
 
     /**
      *
      */
     public function render_audittrail_page($p)
     {
         // append audit trail UI elements to contact page
         if ($p['template'] === 'addressbook' && !$p['kolab-audittrail']) {
             $this->rc->output->add_footer($this->rc->output->parse('kolab_addressbook.audittrail', false, false));
             $p['kolab-audittrail'] = true;
         }
 
         return $p;
     }
 
 
     private function get_form_part($form)
     {
         $content = '';
 
         if (is_array($form['content']) && !empty($form['content'])) {
             $table = new html_table(array('cols' => 2, 'class' => 'propform'));
             foreach ($form['content'] as $col => $colprop) {
                 $colprop['id'] = '_'.$col;
                 $label = !empty($colprop['label']) ? $colprop['label'] : $this->rc->gettext($col);
 
                 $table->add('title', sprintf('<label for="%s">%s</label>', $colprop['id'], rcube::Q($label)));
                 $table->add(null, $colprop['value']);
             }
             $content = $table->show();
         }
         else {
             $content = $form['content'];
         }
 
         return $content;
     }
 
 
     private function get_form_tags($attrib, $action, $id = null, $hidden = null)
     {
         $form_start = $form_end = '';
 
         $request_key = $action . (isset($id) ? '.'.$id : '');
         $form_start = $this->rc->output->request_form(array(
             'name'    => 'form',
             'method'  => 'post',
             'task'    => $this->rc->task,
             'action'  => $action,
             'request' => $request_key,
             'noclose' => true,
         ) + $attrib);
 
         if (is_array($hidden)) {
             foreach ($hidden as $field) {
                 $hiddenfield = new html_hiddenfield($field);
                 $form_start .= $hiddenfield->show();
             }
         }
 
         $form_end = !strlen($attrib['form']) ? '</form>' : '';
 
         $EDIT_FORM = !empty($attrib['form']) ? $attrib['form'] : 'form';
         $this->rc->output->add_gui_object('editform', $EDIT_FORM);
 
         return array($form_start, $form_end);
     }
 
 }
diff --git a/plugins/kolab_notes/kolab_notes_ui.php b/plugins/kolab_notes/kolab_notes_ui.php
index d1cbb759..28e17e8b 100644
--- a/plugins/kolab_notes/kolab_notes_ui.php
+++ b/plugins/kolab_notes/kolab_notes_ui.php
@@ -1,404 +1,399 @@
 <?php
 
 class kolab_notes_ui
 {
     private $rc;
     private $plugin;
     private $ready = false;
 
     function __construct($plugin)
     {
         $this->plugin = $plugin;
         $this->rc = $plugin->rc;
     }
 
     /**
     * Calendar UI initialization and requests handlers
     */
     public function init()
     {
         if ($this->ready)  // already done
             return;
 
         // add taskbar button
         $this->plugin->add_button(array(
             'command'    => 'notes',
             'class'      => 'button-notes',
             'classsel'   => 'button-notes button-selected',
             'innerclass' => 'button-inner',
             'label'      => 'kolab_notes.navtitle',
             'type'       => 'link'
         ), 'taskbar');
 
         $this->plugin->include_stylesheet($this->plugin->local_skin_path() . '/notes.css');
 
         $this->ready = true;
   }
 
     /**
     * Register handler methods for the template engine
     */
     public function init_templates()
     {
         $this->plugin->register_handler('plugin.notebooks', array($this, 'folders'));
         #$this->plugin->register_handler('plugin.folders_select', array($this, 'folders_select'));
         $this->plugin->register_handler('plugin.searchform', array($this->rc->output, 'search_form'));
         $this->plugin->register_handler('plugin.listing', array($this, 'listing'));
         $this->plugin->register_handler('plugin.editform', array($this, 'editform'));
         $this->plugin->register_handler('plugin.notetitle', array($this, 'notetitle'));
         $this->plugin->register_handler('plugin.detailview', array($this, 'detailview'));
         $this->plugin->register_handler('plugin.attachments_list', array($this, 'attachments_list'));
         $this->plugin->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
 
         $this->rc->output->include_script('list.js');
         $this->rc->output->include_script('treelist.js');
         $this->plugin->include_script('notes.js');
-
-        // include kolab folderlist widget if available
-        if (in_array('libkolab', $this->plugin->api->loaded_plugins())) {
-            $this->plugin->api->include_script('libkolab/js/folderlist.js');
-            $this->plugin->api->include_script('libkolab/js/audittrail.js');
-        }
+        $this->plugin->api->include_script('libkolab/libkolab.js');
 
         // load config options and user prefs relevant for the UI
         $settings = array(
             'sort_col' => $this->rc->config->get('kolab_notes_sort_col', 'changed'),
         );
 
         if ($list = rcube_utils::get_input_value('_list', rcube_utils::INPUT_GPC)) {
             $settings['selected_list'] = $list;
         }
         if ($uid = rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC)) {
             $settings['selected_uid'] = $uid;
         }
 
         $this->rc->html_editor();
 
         $this->rc->output->set_env('kolab_notes_settings', $settings);
         $this->rc->output->add_label('save','cancel','delete','close','listoptionstitle');
     }
 
     public function folders($attrib)
     {
         $attrib += array('id' => 'rcmkolabnotebooks');
 
         if ($attrib['type'] == 'select') {
             $attrib['is_escaped'] = true;
             $select = new html_select($attrib);
         }
 
         $tree = $attrib['type'] != 'select' ? true : null;
         $lists = $this->plugin->get_lists($tree);
         $jsenv = array();
 
         if (is_object($tree)) {
             $html = $this->folder_tree_html($tree, $lists, $jsenv, $attrib);
         }
         else {
             $html = '';
             foreach ($lists as $prop) {
                 $id = $prop['id'];
 
                 if (!$prop['virtual']) {
                     unset($prop['user_id']);
                     $jsenv[$id] = $prop;
                 }
 
                 if ($attrib['type'] == 'select') {
                     if ($prop['editable'] || strpos($prop['rights'], 'i') !== false) {
                         $select->add($prop['name'], $prop['id']);
                     }
                 }
                 else {
                     $html .= html::tag('li', array('id' => 'rcmliknb' . rcube_utils::html_identifier($id), 'class' => $prop['group']),
                         $this->folder_list_item($id, $prop, $jsenv)
                     );
                 }
             }
         }
 
         $this->rc->output->set_env('kolab_notebooks', $jsenv);
         $this->rc->output->add_gui_object('notebooks', $attrib['id']);
 
         return $attrib['type'] == 'select' ? $select->show() : html::tag('ul', $attrib, $html, html::$common_attrib);
     }
 
     /**
      * Return html for a structured list <ul> for the folder tree
      */
     public function folder_tree_html($node, $data, &$jsenv, $attrib)
     {
         $out = '';
         foreach ($node->children as $folder) {
             $id = $folder->id;
             $prop = $data[$id];
             $is_collapsed = false; // TODO: determine this somehow?
 
             $content = $this->folder_list_item($id, $prop, $jsenv);
 
             if (!empty($folder->children)) {
                 $content .= html::tag('ul', array('style' => ($is_collapsed ? "display:none;" : null)),
                     $this->folder_tree_html($folder, $data, $jsenv, $attrib));
             }
 
             if (strlen($content)) {
                 $out .= html::tag('li', array(
                       'id' => 'rcmliknb' . rcube_utils::html_identifier($id),
                       'class' => $prop['group'] . ($prop['virtual'] ? ' virtual' : ''),
                     ),
                     $content);
             }
         }
 
         return $out;
     }
 
     /**
      * Helper method to build a tasklist item (HTML content and js data)
      */
     public function folder_list_item($id, $prop, &$jsenv, $checkbox = false)
     {
         if (!$prop['virtual']) {
             unset($prop['user_id']);
             $jsenv[$id] = $prop;
         }
 
         $classes = array('folder');
         if ($prop['virtual']) {
             $classes[] = 'virtual';
         }
         else if (!$prop['editable']) {
             $classes[] = 'readonly';
         }
         if ($prop['subscribed']) {
             $classes[] = 'subscribed';
         }
         if ($prop['class']) {
             $classes[] = $prop['class'];
         }
 
         $title = $prop['title'] ?: ($prop['name'] != $prop['listname'] || strlen($prop['name']) > 25 ?
           html_entity_decode($prop['name'], ENT_COMPAT, RCUBE_CHARSET) : '');
 
         $label_id = 'nl:' . $id;
         $attr = $prop['virtual'] ? array('tabindex' => '0') : array('href' => $this->rc->url(array('_list' => $id)));
         return html::div(join(' ', $classes),
             html::a($attr + array('class' => 'listname', 'title' => $title, 'id' => $label_id), $prop['listname'] ?: $prop['name']) .
             ($prop['virtual'] ? '' :
                 ($checkbox ?
                     html::tag('input', array('type' => 'checkbox', 'name' => '_list[]', 'value' => $id, 'checked' => $prop['active'], 'aria-labelledby' => $label_id)) :
                     ''
                 ) .
                 html::span('handle', '') .
                 html::span('actions',
                     (!$prop['default'] ?
                         html::a(array('href' => '#', 'class' => 'remove', 'title' => $this->plugin->gettext('removelist')), ' ') :
                         ''
                     ) .
                     (isset($prop['subscribed']) ?
                         html::a(array('href' => '#', 'class' => 'subscribed', 'title' => $this->plugin->gettext('foldersubscribe'), 'role' => 'checkbox', 'aria-checked' => $prop['subscribed'] ? 'true' : 'false'), ' ') :
                         ''
                     )
                 )
             )
         );
 
         return '';
     }
 
     public function listing($attrib)
     {
         $attrib += array('id' => 'rcmkolabnoteslist');
         $this->rc->output->add_gui_object('noteslist', $attrib['id']);
         return html::tag('table', $attrib, '<tbody></tbody>', html::$common_attrib);
     }
 
     public function editform($attrib)
     {
         $attrib += array('action' => '#', 'id' => 'rcmkolabnoteseditform');
 
         $textarea = new html_textarea(array(
                 'name'     => 'content',
                 'id'       => 'notecontent',
                 'cols'     => 60,
                 'rows'     => 20,
                 'tabindex' => 0,
                 'class'    => 'mce_editor form-control',
         ));
 
         $this->rc->output->add_gui_object('noteseditform', $attrib['id']);
 
         return html::tag('form', $attrib, $textarea->show(), array_merge(html::$common_attrib, array('action')));
     }
 
     public function detailview($attrib)
     {
         $attrib += array('id' => 'rcmkolabnotesdetailview');
         $this->rc->output->add_gui_object('notesdetailview', $attrib['id']);
         return html::div($attrib, '');
     }
 
     public function notetitle($attrib)
     {
         $attrib += array('id' => 'rcmkolabnotestitle');
         $this->rc->output->add_gui_object('noteviewtitle', $attrib['id']);
 
         $summary = new html_inputfield(array(
                 'name'     => 'summary',
                 'class'    => 'notetitle inline-edit form-control',
                 'size'     => 60,
                 'id'       => 'notetitleinput',
                 'tabindex' => 0
         ));
 
         $html = html::div('form-group row',
                 html::label(array('class' => 'col-sm-2 col-form-label', 'for' => 'notetitleinput'), $this->plugin->gettext('kolab_notes.title'))
                     . html::span('col-sm-10', $summary->show())
             )
             . html::div('form-group row',
                 html::label(array('class' => 'col-sm-2 col-form-label'), $this->plugin->gettext('kolab_notes.tags'))
                     . html::div(array('class' => 'tagline tagedit col-sm-10'), '&nbsp;')
             )
             . html::div(array('class' => 'dates text-only', 'style' => 'display:none'),
                 html::div('form-group row',
                     html::label(array('class' => 'col-sm-2 col-form-label'), $this->plugin->gettext('created'))
                     . html::span('col-sm-10', html::span('notecreated form-control-plaintext', ''))
                 )
                 . html::div('form-group row',
                     html::label(array('class' => 'col-sm-2 col-form-label'), $this->plugin->gettext('changed'))
                     . html::span('col-sm-10', html::span('notechanged form-control-plaintext', ''))
                 )
             );
 
         return html::div($attrib, $html);
     }
 
     public function attachments_list($attrib)
     {
         $attrib += array('id' => 'rcmkolabnotesattachmentslist');
         $this->rc->output->add_gui_object('notesattachmentslist', $attrib['id']);
         return html::tag('ul', $attrib, '', html::$common_attrib);
     }
 
     /**
      * Render create/edit form for notes lists (folders)
      */
     public function list_editform($action, $list, $folder)
     {
         $this->action = $action;
         $this->list   = $list;
         $this->folder = is_object($folder) ? $folder->name : ''; // UTF7;
 
         $this->rc->output->add_handler('notebookform', array($this, 'notebookform'));
         $this->rc->output->send('kolab_notes.listform');
     }
 
     /**
      * Render create/edit form for notes lists (folders)
      */
     public function notebookform($attrib)
     {
         $folder_name     = $this->folder;
         $hidden_fields[] = array('name' => 'oldname', 'value' => $folder_name);
 
         $storage = $this->rc->get_storage();
         $delim   = $storage->get_hierarchy_delimiter();
         $form   = array();
 
         if (strlen($folder_name)) {
             $options = $storage->folder_info($folder_name);
 
             $path_imap = explode($delim, $folder_name);
             array_pop($path_imap);  // pop off name part
             $path_imap = implode($path_imap, $delim);
         }
         else {
             $path_imap = '';
             $options   = array();
         }
 
         // General tab
         $form['properties'] = array(
             'name'   => $this->rc->gettext('properties'),
             'fields' => array(),
         );
 
         // folder name (default field)
         $input_name = new html_inputfield(array('name' => 'name', 'id' => 'noteslist-name', 'size' => 20));
         $form['properties']['fields']['name'] = array(
             'label' => $this->plugin->gettext('listname'),
             'value' => $input_name->show($this->list['editname'], array('disabled' => ($options['norename'] || $options['protected']))),
             'id'    => 'noteslist-name',
         );
 
         // prevent user from moving folder
         if (!empty($options) && ($options['norename'] || $options['protected'])) {
             $hidden_fields[] = array('name' => 'parent', 'value' => $path_imap);
         }
         else {
             $select = kolab_storage::folder_selector('note', array('name' => 'parent', 'id' => 'parent-folder'), $folder_name);
             $form['properties']['fields']['path'] = array(
                 'label' => $this->plugin->gettext('parentfolder'),
                 'value' => $select->show(strlen($folder_name) ? $path_imap : ''),
                 'id'    => 'parent-folder',
             );
         }
 
         // add folder ACL tab
         if ($this->action != 'form-new') {
             $form['sharing'] = array(
                 'name'    => rcube::Q($this->plugin->gettext('tabsharing')),
                 'content' => $this->folder_acl_form()
             );
         }
 
         $form_html = '';
         if (is_array($hidden_fields)) {
             foreach ($hidden_fields as $field) {
                 $hiddenfield = new html_hiddenfield($field);
                 $form_html .= $hiddenfield->show() . "\n";
             }
         }
 
         // create form output
         foreach ($form as $tab) {
             if (is_array($tab['fields']) && empty($tab['content'])) {
                 $table = new html_table(array('cols' => 2, 'class' => 'propform'));
                 foreach ($tab['fields'] as $col => $colprop) {
                     $label = !empty($colprop['label']) ? $colprop['label'] : $this->plugin->gettext($col);
 
                     $table->add('title', html::label($colprop['id'], rcube::Q($label)));
                     $table->add(null, $colprop['value']);
                 }
                 $content = $table->show();
             }
             else {
                 $content = $tab['content'];
             }
 
             if (!empty($content)) {
                 $form_html .= html::tag('fieldset', null, html::tag('legend', null, rcube::Q($tab['name'])) . $content) . "\n";
             }
         }
 
         return html::tag('form', $attrib + array('action' => '#', 'method' => 'post', 'id' => 'noteslistpropform'), $form_html);
     }
 
     /**
      * Returns ACL form
      */
     public function folder_acl_form()
     {
         if (strlen($this->folder)) {
             $this->plugin->require_plugin('acl');
             $storage = $this->rc->get_storage();
             $options = $storage->folder_info($this->folder);
 
             // get sharing UI from acl plugin
             $acl = $this->rc->plugins->exec_hook('folder_form',
                 array('form' => array(), 'options' => $options, 'name' => $this->folder));
         }
 
         return $acl['form']['sharing']['content'] ?: html::div('hint', $this->plugin->gettext('aclnorights'));
     }
 }
diff --git a/plugins/libkolab/js/audittrail.js b/plugins/libkolab/js/audittrail.js
deleted file mode 100644
index 404fc098..00000000
--- a/plugins/libkolab/js/audittrail.js
+++ /dev/null
@@ -1,269 +0,0 @@
-/**
- * Kolab groupware audit trail utilities
- *
- * @author Thomas Bruederli <bruederli@kolabsys.com>
- *
- * @licstart  The following is the entire license notice for the
- * JavaScript code in this file.
- *
- * Copyright (C) 2015, Kolab Systems AG <contact@kolabsys.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- *
- * @licend  The above is the entire license notice
- * for the JavaScript code in this file.
- */
-
-var libkolab_audittrail = {}
-
-libkolab_audittrail.quote_html = function(str)
-{
-    return String(str).replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
-};
-
-
-// show object changelog in a dialog
-libkolab_audittrail.object_history_dialog = function(p)
-{
-    // render dialog
-    var $dialog = $(p.container);
-
-    // close show dialog first
-    if ($dialog.is(':ui-dialog'))
-        $dialog.dialog('close');
-
-    // hide and reset changelog table
-    $dialog.find('div.notfound-message').remove();
-    $dialog.find('.changelog-table').show().children('tbody')
-        .html('<tr><td colspan="4"><span class="loading">' + rcmail.gettext('loading') + '</span></td></tr>');
-
-    // open jquery UI dialog
-    $dialog.dialog({
-        modal: true,
-        resizable: true,
-        closeOnEscape: true,
-        title: p.title,
-        open: function() {
-            $dialog.attr('aria-hidden', 'false');
-        },
-        close: function() {
-            $dialog.dialog('destroy').attr('aria-hidden', 'true').hide();
-        },
-        buttons: [
-            {
-                text: rcmail.gettext('close'),
-                click: function() { $dialog.dialog('close'); },
-                'class': 'cancel',
-                autofocus: true
-            }
-        ],
-        minWidth: 450,
-        width: 650,
-        height: 350,
-        minHeight: 200
-    })
-    .show().children('.compare-button').hide();
-
-    // initialize event handlers for history dialog UI elements
-    if (!$dialog.data('initialized')) {
-      // compare button
-      $dialog.find('.compare-button input').click(function(e) {
-        var rev1 = $dialog.find('.changelog-table input.diff-rev1:checked').val(),
-          rev2 = $dialog.find('.changelog-table input.diff-rev2:checked').val();
-
-          if (rev1 && rev2 && rev1 != rev2) {
-            // swap revisions if the user got it wrong
-            if (rev1 > rev2) {
-              var tmp = rev2;
-              rev2 = rev1;
-              rev1 = tmp;
-            }
-
-            if (p.comparefunc) {
-                p.comparefunc(rev1, rev2);
-            }
-          }
-          else {
-              alert('Invalid selection!')
-          }
-
-          if (!rcube_event.is_keyboard(e) && this.blur) {
-              this.blur();
-          }
-          return false;
-      });
-
-      // delegate handlers for list actions
-      $dialog.find('.changelog-table tbody').on('click', 'td.actions a', function(e) {
-          var link = $(this),
-            action = link.hasClass('restore') ? 'restore' : 'show',
-            event = $('#eventhistory').data('event'),
-            rev = link.attr('data-rev');
-
-            // ignore clicks on first row (current revision)
-            if (link.closest('tr').hasClass('first')) {
-                return false;
-            }
-
-            // let the user confirm the restore action
-            if (action == 'restore' && !confirm(rcmail.gettext('revisionrestoreconfirm', p.module).replace('$rev', rev))) {
-                return false;
-            }
-
-            if (p.listfunc) {
-                p.listfunc(action, rev);
-            }
-
-            if (!rcube_event.is_keyboard(e) && this.blur) {
-                this.blur();
-            }
-            return false;
-      })
-      .on('click', 'input.diff-rev1', function(e) {
-          if (!this.checked) return true;
-
-          var rev1 = this.value, selection_valid = false;
-          $dialog.find('.changelog-table input.diff-rev2').each(function(i, elem) {
-              $(elem).prop('disabled', elem.value <= rev1);
-              if (elem.checked && elem.value > rev1) {
-                  selection_valid = true;
-              }
-          });
-          if (!selection_valid) {
-              $dialog.find('.changelog-table input.diff-rev2:not([disabled])').last().prop('checked', true);
-          }
-      });
-
-      $dialog.addClass('changelog-dialog').data('initialized', true);
-    }
-
-    return $dialog;
-};
-
-// callback from server with changelog data
-libkolab_audittrail.render_changelog = function(data, object, folder)
-{
-    var Q = libkolab_audittrail.quote_html;
-
-    var $dialog = $('.changelog-dialog')
-    if (data === false || !data.length) {
-        return false;
-    }
-
-    var i, change, accessible, op_append,
-      first = data.length - 1, last = 0,
-      is_writeable = !!folder.editable,
-      op_labels = {
-          RECEIVE:   'actionreceive',
-          APPEND:    'actionappend',
-          MOVE:      'actionmove',
-          DELETE:    'actiondelete',
-          READ:      'actionread',
-          FLAGSET:   'actionflagset',
-          FLAGCLEAR: 'actionflagclear'
-      },
-      actions = '<a href="#show" class="iconbutton preview" title="'+ rcmail.gettext('showrevision','libkolab') +'" data-rev="{rev}" /> ' +
-          (is_writeable ? '<a href="#restore" class="iconbutton restore" title="'+ rcmail.gettext('restore','libkolab') + '" data-rev="{rev}" />' : ''),
-      tbody = $dialog.find('.changelog-table tbody').html('');
-
-    for (i=first; i >= 0; i--) {
-        change = data[i];
-        accessible = change.date && change.user;
-
-        if (change.op == 'MOVE' && change.mailbox) {
-            op_append = ' ⇢ ' + change.mailbox;
-        }
-        else if ((change.op == 'FLAGSET' || change.op == 'FLAGCLEAR') && change.flags) {
-            op_append = ': ' + change.flags;
-        }
-        else {
-            op_append = '';
-        }
-
-        $('<tr class="' + (i == first ? 'first' : (i == last ? 'last' : '')) + (accessible ? '' : 'undisclosed') + '">')
-            .append('<td class="diff">' + (accessible && change.op != 'DELETE' ? 
-                '<input type="radio" name="rev1" class="diff-rev1" value="' + change.rev + '" title="" '+ (i == last ? 'checked="checked"' : '') +' /> '+
-                '<input type="radio" name="rev2" class="diff-rev2" value="' + change.rev + '" title="" '+ (i == first ? 'checked="checked"' : '') +' /></td>'
-                : ''))
-            .append('<td class="revision">' + Q(i+1) + '</td>')
-            .append('<td class="date">' + Q(change.date || '') + '</td>')
-            .append('<td class="user">' + Q(change.user || 'undisclosed') + '</td>')
-            .append('<td class="operation" title="' + op_append + '">' + Q(rcmail.gettext(op_labels[change.op] || '', 'libkolab') + op_append) + '</td>')
-            .append('<td class="actions">' + (accessible && change.op != 'DELETE' ? actions.replace(/\{rev\}/g, change.rev) : '') + '</td>')
-            .appendTo(tbody);
-    }
-
-    if (first > 0) {
-        $dialog.find('.compare-button').fadeIn(200);
-        $dialog.find('.changelog-table tr.last input.diff-rev1').click();
-    }
-
-    // set dialog size according to content
-    libkolab_audittrail.dialog_resize($dialog.get(0), $dialog.height() + 15, 600);
-
-    return $dialog;
-};
-
-// resize and reposition (center) the dialog window
-libkolab_audittrail.dialog_resize = function(id, height, width)
-{
-    var win = $(window), w = win.width(), h = win.height();
-    $(id).dialog('option', { height: Math.min(h-20, height+130), width: Math.min(w-20, width+50) });
-};
-
-
-// register handlers for mail message history
-window.rcmail && rcmail.addEventListener('init', function(e) {
-    var loading_lock;
-
-    if (rcmail.env.task == 'mail') {
-        rcmail.register_command('kolab-mail-history', function() {
-            var dialog, uid = rcmail.get_single_uid(), rec = { uid: uid, mbox: rcmail.get_message_mailbox(uid) };
-            if (!uid || !window.libkolab_audittrail) {
-                return false;
-            }
-
-            // render dialog
-            $dialog = libkolab_audittrail.object_history_dialog({
-                module: 'libkolab',
-                container: '#mailmessagehistory',
-                title: rcmail.gettext('objectchangelog','libkolab')
-            });
-
-            $dialog.data('rec', rec);
-
-            // fetch changelog data
-            loading_lock = rcmail.set_busy(true, 'loading', loading_lock);
-            rcmail.http_post('plugin.message-changelog', { _uid: rec.uid, _mbox: rec.mbox }, loading_lock);
-
-        }, rcmail.env.action == 'show');
-
-        rcmail.addEventListener('plugin.message_render_changelog', function(data) {
-            var $dialog = $('#mailmessagehistory'),
-                rec = $dialog.data('rec');
-
-            if (data === false || !data.length || !rec) {
-              // display 'unavailable' message
-              $('<div class="notfound-message dialog-message warning">' + rcmail.gettext('objectchangelognotavailable','libkolab') + '</div>')
-                  .insertBefore($dialog.find('.changelog-table').hide());
-              return;
-            }
-
-            data.module = 'libkolab';
-            libkolab_audittrail.render_changelog(data, rec, {});
-        });
-
-        rcmail.env.message_commands.push('kolab-mail-history');
-    }
-});
diff --git a/plugins/libkolab/js/folderlist.js b/plugins/libkolab/libkolab.js
similarity index 59%
rename from plugins/libkolab/js/folderlist.js
rename to plugins/libkolab/libkolab.js
index 00dcc475..56c8dee7 100644
--- a/plugins/libkolab/js/folderlist.js
+++ b/plugins/libkolab/libkolab.js
@@ -1,359 +1,617 @@
 /**
- * Kolab groupware folders treelist widget
+ * Kolab groupware utilities
  *
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * @licstart  The following is the entire license notice for the
  * JavaScript code in this file.
  *
- * Copyright (C) 2014, Kolab Systems AG <contact@kolabsys.com>
+ * Copyright (C) 2015-2018, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  *
  * @licend  The above is the entire license notice
  * for the JavaScript code in this file.
  */
 
+var libkolab_audittrail = {}
+
+libkolab_audittrail.quote_html = function(str)
+{
+    return String(str).replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
+};
+
+// show object changelog in a dialog
+libkolab_audittrail.object_history_dialog = function(p)
+{
+    // render dialog
+    var $dialog = $(p.container);
+
+    // close show dialog first
+    if ($dialog.is(':ui-dialog'))
+        $dialog.dialog('close');
+
+    // hide and reset changelog table
+    $dialog.find('div.notfound-message').remove();
+    $dialog.find('.changelog-table').show().children('tbody')
+        .html('<tr><td colspan="4"><span class="loading">' + rcmail.gettext('loading') + '</span></td></tr>');
+
+    // open jquery UI dialog
+    $dialog.dialog({
+        modal: true,
+        resizable: true,
+        closeOnEscape: true,
+        title: p.title,
+        open: function() {
+            $dialog.attr('aria-hidden', 'false');
+        },
+        close: function() {
+            $dialog.dialog('destroy').attr('aria-hidden', 'true').hide();
+        },
+        buttons: [
+            {
+                text: rcmail.gettext('close'),
+                click: function() { $dialog.dialog('close'); },
+                'class': 'cancel',
+                autofocus: true
+            }
+        ],
+        minWidth: 450,
+        width: 650,
+        height: 350,
+        minHeight: 200
+    })
+    .show().children('.compare-button').hide();
+
+    // initialize event handlers for history dialog UI elements
+    if (!$dialog.data('initialized')) {
+      // compare button
+      $dialog.find('.compare-button input').click(function(e) {
+        var rev1 = $dialog.find('.changelog-table input.diff-rev1:checked').val(),
+          rev2 = $dialog.find('.changelog-table input.diff-rev2:checked').val();
+
+          if (rev1 && rev2 && rev1 != rev2) {
+            // swap revisions if the user got it wrong
+            if (rev1 > rev2) {
+              var tmp = rev2;
+              rev2 = rev1;
+              rev1 = tmp;
+            }
+
+            if (p.comparefunc) {
+                p.comparefunc(rev1, rev2);
+            }
+          }
+          else {
+              alert('Invalid selection!')
+          }
+
+          if (!rcube_event.is_keyboard(e) && this.blur) {
+              this.blur();
+          }
+          return false;
+      });
+
+      // delegate handlers for list actions
+      $dialog.find('.changelog-table tbody').on('click', 'td.actions a', function(e) {
+          var link = $(this),
+            action = link.hasClass('restore') ? 'restore' : 'show',
+            event = $('#eventhistory').data('event'),
+            rev = link.attr('data-rev');
+
+            // ignore clicks on first row (current revision)
+            if (link.closest('tr').hasClass('first')) {
+                return false;
+            }
+
+            // let the user confirm the restore action
+            if (action == 'restore' && !confirm(rcmail.gettext('revisionrestoreconfirm', p.module).replace('$rev', rev))) {
+                return false;
+            }
+
+            if (p.listfunc) {
+                p.listfunc(action, rev);
+            }
+
+            if (!rcube_event.is_keyboard(e) && this.blur) {
+                this.blur();
+            }
+            return false;
+      })
+      .on('click', 'input.diff-rev1', function(e) {
+          if (!this.checked) return true;
+
+          var rev1 = this.value, selection_valid = false;
+          $dialog.find('.changelog-table input.diff-rev2').each(function(i, elem) {
+              $(elem).prop('disabled', elem.value <= rev1);
+              if (elem.checked && elem.value > rev1) {
+                  selection_valid = true;
+              }
+          });
+          if (!selection_valid) {
+              $dialog.find('.changelog-table input.diff-rev2:not([disabled])').last().prop('checked', true);
+          }
+      });
+
+      $dialog.addClass('changelog-dialog').data('initialized', true);
+    }
+
+    return $dialog;
+};
+
+// callback from server with changelog data
+libkolab_audittrail.render_changelog = function(data, object, folder)
+{
+    var Q = libkolab_audittrail.quote_html;
+
+    var $dialog = $('.changelog-dialog')
+    if (data === false || !data.length) {
+        return false;
+    }
+
+    var i, change, accessible, op_append,
+      first = data.length - 1, last = 0,
+      is_writeable = !!folder.editable,
+      op_labels = {
+          RECEIVE:   'actionreceive',
+          APPEND:    'actionappend',
+          MOVE:      'actionmove',
+          DELETE:    'actiondelete',
+          READ:      'actionread',
+          FLAGSET:   'actionflagset',
+          FLAGCLEAR: 'actionflagclear'
+      },
+      actions = '<a href="#show" class="iconbutton preview" title="'+ rcmail.gettext('showrevision','libkolab') +'" data-rev="{rev}" /> ' +
+          (is_writeable ? '<a href="#restore" class="iconbutton restore" title="'+ rcmail.gettext('restore','libkolab') + '" data-rev="{rev}" />' : ''),
+      tbody = $dialog.find('.changelog-table tbody').html('');
+
+    for (i=first; i >= 0; i--) {
+        change = data[i];
+        accessible = change.date && change.user;
+
+        if (change.op == 'MOVE' && change.mailbox) {
+            op_append = ' ⇢ ' + change.mailbox;
+        }
+        else if ((change.op == 'FLAGSET' || change.op == 'FLAGCLEAR') && change.flags) {
+            op_append = ': ' + change.flags;
+        }
+        else {
+            op_append = '';
+        }
+
+        $('<tr class="' + (i == first ? 'first' : (i == last ? 'last' : '')) + (accessible ? '' : 'undisclosed') + '">')
+            .append('<td class="diff">' + (accessible && change.op != 'DELETE' ? 
+                '<input type="radio" name="rev1" class="diff-rev1" value="' + change.rev + '" title="" '+ (i == last ? 'checked="checked"' : '') +' /> '+
+                '<input type="radio" name="rev2" class="diff-rev2" value="' + change.rev + '" title="" '+ (i == first ? 'checked="checked"' : '') +' /></td>'
+                : ''))
+            .append('<td class="revision">' + Q(i+1) + '</td>')
+            .append('<td class="date">' + Q(change.date || '') + '</td>')
+            .append('<td class="user">' + Q(change.user || 'undisclosed') + '</td>')
+            .append('<td class="operation" title="' + op_append + '">' + Q(rcmail.gettext(op_labels[change.op] || '', 'libkolab') + op_append) + '</td>')
+            .append('<td class="actions">' + (accessible && change.op != 'DELETE' ? actions.replace(/\{rev\}/g, change.rev) : '') + '</td>')
+            .appendTo(tbody);
+    }
+
+    if (first > 0) {
+        $dialog.find('.compare-button').fadeIn(200);
+        $dialog.find('.changelog-table tr.last input.diff-rev1').click();
+    }
+
+    // set dialog size according to content
+    libkolab_audittrail.dialog_resize($dialog.get(0), $dialog.height() + 15, 600);
+
+    return $dialog;
+};
+
+// resize and reposition (center) the dialog window
+libkolab_audittrail.dialog_resize = function(id, height, width)
+{
+    var win = $(window), w = win.width(), h = win.height();
+    $(id).dialog('option', { height: Math.min(h-20, height+130), width: Math.min(w-20, width+50) });
+};
+
 function kolab_folderlist(node, p)
 {
     // extends treelist.js
     rcube_treelist_widget.call(this, node, p);
 
     // private vars
     var me = this;
     var search_results;
     var search_results_widget;
     var search_results_container;
     var listsearch_request;
     var search_messagebox;
 
     var Q = rcmail.quote_html;
 
     // render the results for folderlist search
     function render_search_results(results)
     {
         if (results.length) {
           // create treelist widget to present the search results
           if (!search_results_widget) {
               var list_id = (me.container.attr('id') || p.id_prefix || '0');
 
               search_results_container = $('<div class="searchresults"></div>')
                   .html(p.search_title ? '<h2 class="boxtitle" id="st:' + list_id + '">' + p.search_title + '</h2>' : '')
                   .insertAfter(me.container);
 
               search_results_widget = new rcube_treelist_widget('<ul>', {
                   id_prefix: p.id_prefix,
                   id_encode: p.id_encode,
                   id_decode: p.id_decode,
                   selectable: false
               });
 
               // copy classes from main list
               search_results_widget.container.addClass(me.container.attr('class')).attr('aria-labelledby', 'st:' + list_id);
 
               // register click handler on search result's checkboxes to select the given item for listing
               search_results_widget.container
                   .appendTo(search_results_container)
                   .on('click', 'input[type=checkbox], a.subscribed, span.subscribed', function(e) {
                       var node, has_children, li = $(this).closest('li'),
                           id = li.attr('id').replace(new RegExp('^'+p.id_prefix), '');
 
                       if (p.id_decode)
                           id = p.id_decode(id);
                       node = search_results_widget.get_node(id);
                       has_children = node.children && node.children.length;
 
                       e.stopPropagation();
                       e.bubbles = false;
 
                       // activate + subscribe
                       if ($(e.target).hasClass('subscribed')) {
                           search_results[id].subscribed = true;
                           $(e.target).attr('aria-checked', 'true');
                           li.children().first()
                               .toggleClass('subscribed')
                               .find('input[type=checkbox]').get(0).checked = true;
 
                           if (has_children && search_results[id].group == 'other user') {
                               li.find('ul li > div').addClass('subscribed')
                                   .find('a.subscribed').attr('aria-checked', 'true');;
                           }
                       }
                       else if (!this.checked) {
                           return;
                       }
 
                       // copy item to the main list
                       add_result2list(id, li, true);
 
                       if (has_children) {
                           li.find('input[type=checkbox]').first().prop('disabled', true).prop('checked', true);
                           li.find('a.subscribed, span.subscribed').first().hide();
                       }
                       else {
                           li.remove();
                       }
 
                       // set partial subscription status
                       if (search_results[id].subscribed && search_results[id].parent && search_results[id].group == 'other') {
                           parent_subscription_status($(me.get_item(id, true)));
                       }
 
                       // set focus to cloned checkbox
                       if (rcube_event.is_keyboard(e)) {
                           $(me.get_item(id, true)).find('input[type=checkbox]').first().focus();
                       }
                   })
                   .on('click', function(e) {
                       var prop, id = String($(e.target).closest('li').attr('id')).replace(new RegExp('^'+p.id_prefix), '');
                       if (p.id_decode)
                           id = p.id_decode(id);
 
                       if (!rcube_event.is_keyboard(e) && e.target.blur)
                         e.target.blur();
 
                       // forward event
                       if (prop = search_results[id]) {
                         e.data = prop;
                         if (me.triggerEvent('click-item', e) === false) {
                           e.stopPropagation();
                           return false;
                         }
                       }
                   });
           }
 
           // add results to list
           for (var prop, item, i=0; i < results.length; i++) {
               prop = results[i];
               item = $(prop.html);
               search_results[prop.id] = prop;
               search_results_widget.insert({
                   id: prop.id,
                   classes: [ prop.group || '' ],
                   html: item,
                   collapsed: true,
                   virtual: prop.virtual
               }, prop.parent);
 
               // disable checkbox if item already exists in main list
               if (me.get_node(prop.id) && !me.get_node(prop.id).virtual) {
                   item.find('input[type=checkbox]').first().prop('disabled', true).prop('checked', true);
                   item.find('a.subscribed, span.subscribed').hide();
               }
 
               prop.li = item.parent().get(0);
               me.triggerEvent('add-item', prop);
           }
 
           search_results_container.show();
         }
     }
 
     // helper method to (recursively) add a search result item to the main list widget
     function add_result2list(id, li, active)
     {
         var node = search_results_widget.get_node(id),
             prop = search_results[id],
             parent_id = prop.parent || null,
             has_children = node.children && node.children.length,
             dom_node = has_children ? li.children().first().clone(true, true) : li.children().first(),
             childs = [];
 
         // find parent node and insert at the right place
         if (parent_id && me.get_node(parent_id)) {
             dom_node.children('span,a').first().html(Q(prop.editname || prop.listname));
         }
         else if (parent_id && search_results[parent_id]) {
             // copy parent tree from search results
             add_result2list(parent_id, $(search_results_widget.get_item(parent_id)), false);
         }
         else if (parent_id) {
             // use full name for list display
             dom_node.children('span,a').first().html(Q(prop.name));
         }
 
         // replace virtual node with a real one
         if (me.get_node(id)) {
             $(me.get_item(id, true)).children().first()
                 .replaceWith(dom_node)
                 .removeClass('virtual');
         }
         else {
             // copy childs, too
             if (has_children && prop.group == 'other user') {
                 for (var cid, j=0; j < node.children.length; j++) {
                     if ((cid = node.children[j].id) && search_results[cid]) {
                         childs.push(search_results_widget.get_node(cid));
                     }
                 }
             }
 
             // move this result item to the main list widget
             me.insert({
                 id: id,
                 classes: [ prop.group || '' ],
                 virtual: prop.virtual,
                 html: dom_node,
                 level: node.level,
                 collapsed: true,
                 children: childs
             }, parent_id, prop.group);
         }
 
         delete prop.html;
         prop.active = active;
         me.triggerEvent('insert-item', { id: id, data: prop, item: li });
 
         // register childs, too
         if (childs.length) {
             for (var cid, j=0; j < node.children.length; j++) {
                 if ((cid = node.children[j].id) && search_results[cid]) {
                     prop = search_results[cid];
                     delete prop.html;
                     prop.active = false;
                     me.triggerEvent('insert-item', { id: cid, data: prop });
                 }
             }
         }
     }
 
     // update the given item's parent's (partial) subscription state
     function parent_subscription_status(li)
     {
         var top_li = li.closest(me.container.children('li')),
             all_childs = $('li > div:not(.treetoggle)', top_li),
             subscribed = all_childs.filter('.subscribed').length;
 
         if (subscribed == 0) {
             top_li.children('div:first').removeClass('subscribed partial');
         }
         else {
             top_li.children('div:first')
                 .addClass('subscribed')[subscribed < all_childs.length ? 'addClass' : 'removeClass']('partial');
         }
     }
 
     // do some magic when search is performed on the widget
     this.addEventListener('search', function(search) {
         // hide search results
         if (search_results_widget) {
             search_results_container.hide();
             search_results_widget.reset();
         }
         search_results = {};
 
         if (search_messagebox)
             rcmail.hide_message(search_messagebox);
 
         // send search request(s) to server
         if (search.query && search.execute) {
             // require a minimum length for the search string
             if (rcmail.env.autocomplete_min_length && search.query.length < rcmail.env.autocomplete_min_length && search.query != '*') {
                 search_messagebox = rcmail.display_message(
                     rcmail.get_label('autocompletechars').replace('$min', rcmail.env.autocomplete_min_length));
                 return;
             }
 
             if (listsearch_request) {
                 // ignore, let the currently running request finish
                 if (listsearch_request.query == search.query) {
                     return;
                 }
                 else { // cancel previous search request
                     rcmail.multi_thread_request_abort(listsearch_request.id);
                     listsearch_request = null;
                 }
             }
 
             var sources = p.search_sources || [ 'folders' ];
             var reqid = rcmail.multi_thread_http_request({
                 items: sources,
                 threads: rcmail.env.autocomplete_threads || 1,
                 action:  p.search_action || 'listsearch',
                 postdata: { action:'search', q:search.query, source:'%s' },
                 lock: rcmail.display_message(rcmail.get_label('searching'), 'loading'),
                 onresponse: render_search_results,
                 whendone: function(data){
                   listsearch_request = null;
                   me.triggerEvent('search-complete', data);
                 }
             });
 
             listsearch_request = { id:reqid, query:search.query };
         }
         else if (!search.query && listsearch_request) {
             rcmail.multi_thread_request_abort(listsearch_request.id);
             listsearch_request = null;
         }
     });
 
     this.container.on('click', 'a.subscribed, span.subscribed', function(e) {
         var li = $(this).closest('li'),
             id = li.attr('id').replace(new RegExp('^'+p.id_prefix), ''),
             div = li.children().first(),
             is_subscribed;
 
         if (me.is_search()) {
             id = id.replace(/--xsR$/, '');
             li = $(me.get_item(id, true));
             div = $(div).add(li.children().first());
         }
 
         if (p.id_decode)
             id = p.id_decode(id);
 
         div.toggleClass('subscribed');
         is_subscribed = div.hasClass('subscribed');
         $(this).attr('aria-checked', is_subscribed ? 'true' : 'false');
         me.triggerEvent('subscribe', { id: id, subscribed: is_subscribed, item: li });
 
         // update subscribe state of all 'virtual user' child folders
         if (li.hasClass('other user')) {
             $('ul li > div', li).each(function() {
                 $(this)[is_subscribed ? 'addClass' : 'removeClass']('subscribed');
                 $('.subscribed', div).attr('aria-checked', is_subscribed ? 'true' : 'false');
             });
             div.removeClass('partial');
         }
         // propagate subscription state to parent  'virtual user' folder
         else if (li.closest('li.other.user').length) {
             parent_subscription_status(li);
         }
 
         e.stopPropagation();
         return false;
     });
 
     this.container.on('click', 'a.remove', function(e) {
       var li = $(this).closest('li'),
           id = li.attr('id').replace(new RegExp('^'+p.id_prefix), '');
 
       if (me.is_search()) {
           id = id.replace(/--xsR$/, '');
           li = $(me.get_item(id, true));
       }
 
       if (p.id_decode)
           id = p.id_decode(id);
 
       me.triggerEvent('remove', { id: id, item: li });
 
       e.stopPropagation();
       return false;
     });
 }
 
 // link prototype from base class
 kolab_folderlist.prototype = rcube_treelist_widget.prototype;
+
+
+window.rcmail && rcmail.addEventListener('init', function(e) {
+    var loading_lock;
+
+    if (rcmail.env.task == 'mail') {
+        rcmail.register_command('kolab-mail-history', function() {
+            var dialog, uid = rcmail.get_single_uid(), rec = { uid: uid, mbox: rcmail.get_message_mailbox(uid) };
+            if (!uid || !window.libkolab_audittrail) {
+                return false;
+            }
+
+            // render dialog
+            $dialog = libkolab_audittrail.object_history_dialog({
+                module: 'libkolab',
+                container: '#mailmessagehistory',
+                title: rcmail.gettext('objectchangelog','libkolab')
+            });
+
+            $dialog.data('rec', rec);
+
+            // fetch changelog data
+            loading_lock = rcmail.set_busy(true, 'loading', loading_lock);
+            rcmail.http_post('plugin.message-changelog', { _uid: rec.uid, _mbox: rec.mbox }, loading_lock);
+
+        }, rcmail.env.action == 'show');
+
+        rcmail.addEventListener('plugin.message_render_changelog', function(data) {
+            var $dialog = $('#mailmessagehistory'),
+                rec = $dialog.data('rec');
+
+            if (data === false || !data.length || !rec) {
+              // display 'unavailable' message
+              $('<div class="notfound-message dialog-message warning">' + rcmail.gettext('objectchangelognotavailable','libkolab') + '</div>')
+                  .insertBefore($dialog.find('.changelog-table').hide());
+              return;
+            }
+
+            data.module = 'libkolab';
+            libkolab_audittrail.render_changelog(data, rec, {});
+        });
+
+        rcmail.env.message_commands.push('kolab-mail-history');
+    }
+
+    if (rcmail.env.action == 'get-attachment') {
+        if (rcmail.rcmail.gui_objects.attachmentframe) {
+            rcmail.gui_objects.messagepartframe = rcmail.gui_objects.attachmentframe;
+            rcmail.enable_command('image-scale', 'image-rotate', !!/^image\//.test(rcmail.env.mimetype));
+            rcmail.register_command('print-attachment', function() {
+                var frame = rcmail.get_frame_window(rcmail.gui_objects.attachmentframe.id);
+                if (frame) frame.print();
+            }, true);
+        }
+
+        if (rcmail.env.attachment_download_url) {
+            rcmail.register_command('download-attachment', function() {
+                rcmail.location_href(rcmail.env.attachment_download_url, window);
+            }, true);
+        }
+    }
+});
diff --git a/plugins/libkolab/libkolab.php b/plugins/libkolab/libkolab.php
index cee2df9c..27691fd5 100644
--- a/plugins/libkolab/libkolab.php
+++ b/plugins/libkolab/libkolab.php
@@ -1,345 +1,345 @@
 <?php
 
 /**
  * Kolab core library
  *
  * Plugin to setup a basic environment for the interaction with a Kolab server.
  * Other Kolab-related plugins will depend on it and can use the library classes
  *
  * @version @package_version@
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2012-2015, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 class libkolab extends rcube_plugin
 {
     static $http_requests = array();
     static $bonnie_api = false;
 
     /**
      * Required startup method of a Roundcube plugin
      */
     public function init()
     {
         // load local config
         $this->load_config();
 
         // extend include path to load bundled lib classes
         $include_path = $this->home . '/lib' . PATH_SEPARATOR . ini_get('include_path');
         set_include_path($include_path);
 
         $this->add_hook('storage_init', array($this, 'storage_init'));
         $this->add_hook('storage_connect', array($this, 'storage_connect'));
         $this->add_hook('user_delete', array('kolab_storage', 'delete_user_folders'));
 
         $rcmail = rcube::get_instance();
         try {
             kolab_format::$timezone = new DateTimeZone($rcmail->config->get('timezone', 'GMT'));
         }
         catch (Exception $e) {
             rcube::raise_error($e, true);
             kolab_format::$timezone = new DateTimeZone('GMT');
         }
 
         $this->add_texts('localization/', false);
 
         if ($rcmail->output->type == 'html') {
             $this->include_stylesheet($this->local_skin_path() . '/libkolab.css');
         }
 
         // embed scripts and templates for email message audit trail
         if ($rcmail->task == 'mail' && self::get_bonnie_api()) {
             if ($rcmail->output->type == 'html') {
                 $this->add_hook('render_page', array($this, 'bonnie_render_page'));
-                $this->include_script('js/audittrail.js');
+                $this->include_script('libkolab.js');
 
                 // add 'Show history' item to message menu
                 $this->api->add_content(html::tag('li', null,
                     $this->api->output->button(array(
                         'command'  => 'kolab-mail-history',
                         'label'    => 'libkolab.showhistory',
                         'type'     => 'link',
                         'classact' => 'icon history active',
                         'class'    => 'icon history',
                         'innerclass' => 'icon history',
                     ))),
                     'messagemenu');
             }
 
             $this->register_action('plugin.message-changelog', array($this, 'message_changelog'));
         }
     }
 
     /**
      * Hook into IMAP FETCH HEADER.FIELDS command and request Kolab-specific headers
      */
     function storage_init($p)
     {
         $p['fetch_headers'] = trim($p['fetch_headers'] .' X-KOLAB-TYPE X-KOLAB-MIME-VERSION MESSAGE-ID');
         return $p;
     }
 
     /**
      * Hook into IMAP connection to replace client identity
      */
     function storage_connect($p)
     {
         $client_name = 'Roundcube/Kolab';
 
         if (empty($p['ident'])) {
             $p['ident'] = array(
                 'name'    => $client_name,
                 'version' => RCUBE_VERSION,
 /*
                 'php'     => PHP_VERSION,
                 'os'      => PHP_OS,
                 'command' => $_SERVER['REQUEST_URI'],
 */
             );
         }
         else {
             $p['ident']['name'] = $client_name;
         }
 
         return $p;
     }
 
     /**
      * Getter for a singleton instance of the Bonnie API
      *
      * @return mixed kolab_bonnie_api instance if configured, false otherwise
      */
     public static function get_bonnie_api()
     {
         // get configuration for the Bonnie API
         if (!self::$bonnie_api && ($bonnie_config = rcube::get_instance()->config->get('kolab_bonnie_api', false))) {
             self::$bonnie_api = new kolab_bonnie_api($bonnie_config);
         }
 
         return self::$bonnie_api;
     }
 
     /**
      * Hook to append the message history dialog template to the mail view
      */
     function bonnie_render_page($p)
     {
         if (($p['template'] === 'mail' || $p['template'] === 'message') && !$p['kolab-audittrail']) {
             // append a template for the audit trail dialog
             $this->api->output->add_footer(
                 html::div(array('id' => 'mailmessagehistory',  'class' => 'uidialog', 'aria-hidden' => 'true', 'style' => 'display:none'),
                     self::object_changelog_table(array('class' => 'records-table changelog-table'))
                 )
             );
             $this->api->output->set_env('kolab_audit_trail', true);
             $p['kolab-audittrail'] = true;
         }
 
         return $p;
     }
 
     /**
      * Handler for message audit trail changelog requests
      */
     public function message_changelog()
     {
         if (!self::$bonnie_api) {
             return false;
         }
 
         $rcmail = rcube::get_instance();
         $msguid = rcube_utils::get_input_value('_uid', rcube_utils::INPUT_POST, true);
         $mailbox = rcube_utils::get_input_value('_mbox', rcube_utils::INPUT_POST);
 
         $result = $msguid && $mailbox ? self::$bonnie_api->changelog('mail', null, $mailbox, $msguid) : null;
         if (is_array($result)) {
             if (is_array($result['changes'])) {
                 $dtformat = $rcmail->config->get('date_format') . ' ' . $rcmail->config->get('time_format');
                 array_walk($result['changes'], function(&$change) use ($dtformat, $rcmail) {
                   if ($change['date']) {
                       $dt = rcube_utils::anytodatetime($change['date']);
                       if ($dt instanceof DateTime) {
                           $change['date'] = $rcmail->format_date($dt, $dtformat);
                       }
                   }
                 });
             }
             $this->api->output->command('plugin.message_render_changelog', $result['changes']);
         }
         else {
             $this->api->output->command('plugin.message_render_changelog', false);
         }
 
         $this->api->output->send();
     }
 
     /**
      * Wrapper function to load and initalize the HTTP_Request2 Object
      *
      * @param string|Net_Url2 Request URL
      * @param string          Request method ('OPTIONS','GET','HEAD','POST','PUT','DELETE','TRACE','CONNECT')
      * @param array           Configuration for this Request instance, that will be merged
      *                        with default configuration
      *
      * @return HTTP_Request2 Request object
      */
     public static function http_request($url = '', $method = 'GET', $config = array())
     {
         $rcube       = rcube::get_instance();
         $http_config = (array) $rcube->config->get('kolab_http_request');
 
         // deprecated configuration options
         if (empty($http_config)) {
             foreach (array('ssl_verify_peer', 'ssl_verify_host') as $option) {
                 $value = $rcube->config->get('kolab_' . $option, true);
                 if (is_bool($value)) {
                     $http_config[$option] = $value;
                 }
             }
         }
 
         if (!empty($config)) {
             $http_config = array_merge($http_config, $config);
         }
 
         // force CURL adapter, this allows to handle correctly
         // compressed responses with SplObserver registered (kolab_files) (#4507)
         $http_config['adapter'] = 'HTTP_Request2_Adapter_Curl';
 
         $key = md5(serialize($http_config));
 
         if (!($request = self::$http_requests[$key])) {
             // load HTTP_Request2
             require_once 'HTTP/Request2.php';
 
             try {
                 $request = new HTTP_Request2();
                 $request->setConfig($http_config);
             }
             catch (Exception $e) {
                 rcube::raise_error($e, true, true);
             }
 
             // proxy User-Agent string
             $request->setHeader('user-agent', $_SERVER['HTTP_USER_AGENT']);
 
             self::$http_requests[$key] = $request;
         }
 
         // cleanup
         try {
             $request->setBody('');
             $request->setUrl($url);
             $request->setMethod($method);
         }
         catch (Exception $e) {
             rcube::raise_error($e, true, true);
         }
 
         return $request;
     }
 
     /**
      * Table oultine for object changelog display
      */
     public static function object_changelog_table($attrib = array())
     {
         $rcube = rcube::get_instance();
         $attrib += array('domain' => 'libkolab');
 
         $table = new html_table(array('cols' => 5, 'border' => 0, 'cellspacing' => 0));
         $table->add_header('diff',      '');
         $table->add_header('revision',  $rcube->gettext('revision', $attrib['domain']));
         $table->add_header('date',      $rcube->gettext('date', $attrib['domain']));
         $table->add_header('user',      $rcube->gettext('user', $attrib['domain']));
         $table->add_header('operation', $rcube->gettext('operation', $attrib['domain']));
         $table->add_header('actions',   '&nbsp;');
 
         $rcube->output->add_label(
             'libkolab.showrevision',
             'libkolab.actionreceive',
             'libkolab.actionappend',
             'libkolab.actionmove',
             'libkolab.actiondelete',
             'libkolab.actionread',
             'libkolab.actionflagset',
             'libkolab.actionflagclear',
             'libkolab.objectchangelog',
             'libkolab.objectchangelognotavailable',
             'close'
         );
 
         return $table->show($attrib);
     }
 
     /**
      * Wrapper function for generating a html diff using the FineDiff class by Raymond Hill
      */
     public static function html_diff($from, $to, $is_html = null)
     {
         // auto-detect text/html format
         if ($is_html === null) {
             $from_html = (preg_match('/<(html|body)(\s+[a-z]|>)/', $from, $m) && strpos($from, '</'.$m[1].'>') > 0);
             $to_html   = (preg_match('/<(html|body)(\s+[a-z]|>)/', $to, $m) && strpos($to, '</'.$m[1].'>') > 0);
             $is_html   = $from_html || $to_html;
 
             // ensure both parts are of the same format
             if ($is_html && !$from_html) {
                 $converter = new rcube_text2html($from, false, array('wrap' => true));
                 $from = $converter->get_html();
             }
             if ($is_html && !$to_html) {
                 $converter = new rcube_text2html($to, false, array('wrap' => true));
                 $to = $converter->get_html();
             }
         }
 
         // compute diff from HTML
         if ($is_html) {
             include_once __dir__ . '/vendor/Caxy/HtmlDiff/Match.php';
             include_once __dir__ . '/vendor/Caxy/HtmlDiff/Operation.php';
             include_once __dir__ . '/vendor/Caxy/HtmlDiff/HtmlDiff.php';
 
             // replace data: urls with a transparent image to avoid memory problems
             $from = preg_replace('/src="data:image[^"]+/', 'src="data:image/gif;base64,R0lGODlhAQABAPAAAOjq6gAAACH/C1hNUCBEYXRhWE1QAT8AIfkEBQAAAAAsAAAAAAEAAQAAAgJEAQA7', $from);
             $to   = preg_replace('/src="data:image[^"]+/', 'src="data:image/gif;base64,R0lGODlhAQABAPAAAOjq6gAAACH/C1hNUCBEYXRhWE1QAT8AIfkEBQAAAAAsAAAAAAEAAQAAAgJEAQA7', $to);
 
             $diff = new Caxy\HtmlDiff\HtmlDiff($from, $to);
             $diffhtml = $diff->build();
 
             // remove empty inserts (from tables)
             return preg_replace('!<ins class="diff\w+">\s*</ins>!Uims', '', $diffhtml);
         }
         else {
             include_once __dir__ . '/vendor/finediff.php';
 
             $diff = new FineDiff($from, $to, FineDiff::$wordGranularity);
             return $diff->renderDiffToHTML();
         }
     }
 
     /**
      * Return a date() format string to render identifiers for recurrence instances
      *
      * @param array Hash array with event properties
      * @return string Format string
      */
     public static function recurrence_id_format($event)
     {
         return $event['allday'] ? 'Ymd' : 'Ymd\THis';
     }
 }
diff --git a/plugins/libkolab/skins/elastic/templates/attachment.html b/plugins/libkolab/skins/elastic/templates/attachment.html
index eb4d6950..e81fabe4 100644
--- a/plugins/libkolab/skins/elastic/templates/attachment.html
+++ b/plugins/libkolab/skins/elastic/templates/attachment.html
@@ -1,86 +1,67 @@
 <roundcube:include file="includes/layout.html" />
 
 <h1 class="voice"><roundcube:var name="env:filename" /></h1>
 
 <div class="sidebar listbox">
 	<div class="header">
 		<a class="button icon back-content-button" href="#content" data-hidden="big"><span class="inner"><roundcube:label name="back" /></span></a>
 		<span class="header-title" id="aria-label-contentinfo"><roundcube:label name="properties" /></span>
 	</div>
 	<roundcube:object name="plugin.attachmentcontrols" class="listing" role="contentinfo"
 		aria-labelledby="aria-label-contentinfo" />
 </div>
 
 <div class="content selected">
 	<h2 id="aria-label-toolbar" class="voice"><roundcube:label name="arialabeltoolbar" /></h2>
 	<div class="header" role="toolbar" aria-labelledby="aria-label-toolbar">
 		<span class="header-title constant"><roundcube:var name="env:filename" /></span>
 		<div id="messagetoolbar" class="toolbar">
 			<a class="button properties" id="properties-button" href="#properties" onclick="UI.show_sidebar()" data-hidden="big">
 				<span class="inner"><roundcube:label name="properties"></span>
 			</a>
 			<roundcube:button command="download-attachment" type="link" label="download" title="download"
 				class="button download disabled" classAct="button download" innerclass="inner" />
 			<roundcube:button command="print-attachment" type="link" label="print" title="print"
 				class="button print disabled" classAct="button print" innerclass="inner" data-hidden="small" />
 			<roundcube:if condition="stripos(env:mimetype, 'image/') === 0" />
 				<roundcube:button command="image-scale" type="link" prop="+" data-hidden="small"
 					class="button zoomin disabled" classAct="button zoomin"
 					label="zoomin" title="increaseimage" innerclass="inner" />
 				<roundcube:button command="image-scale" type="link" prop="-" data-hidden="small"
 					class="button zoomout disabled" classAct="button zoomout"
 					label="zoomout" title="decreaseimage" innerclass="inner" />
 				<roundcube:button command="image-rotate" type="link"
 					class="button rotate disabled" classAct="button rotate" data-hidden="small"
 					label="rotate" title="rotateimage" innerclass="inner" />
 			<roundcube:endif />
 		</div>
 	</div>
 	<h2 id="aria-label-messagepart" class="voice"><roundcube:label name="arialabelattachmentpreview" /></h2>
 	<div class="iframe-wrapper">
 		<roundcube:object name="plugin.attachmentframe" id="attachmentframe" title="arialabelattachmentpreview"
 			role="main" aria-labelledby="aria-label-messagepart" />
 	</div>
 </div>
 
 <roundcube:if condition="stripos(env:mimetype, 'image/') === 0" />
 	<div id="image-tools" class="image-tools" data-hidden="big">
 		<h3 id="aria-label-imagetools" class="voice"><roundcube:label name="arialabelimagetools" /></h3>
 		<div class="toolbar" role="menu" aria-labelledby="aria-label-imagetools">
 			<roundcube:button command="image-scale" type="link" prop="+"
 				class="button zoomin disabled" classAct="button zoomin"
 				label="zoomin" title="increaseimage" innerclass="inner" />
 			<roundcube:button command="image-scale" type="link" prop="-"
 				class="button zoomout disabled" classAct="button zoomout"
 				label="zoomout" title="decreaseimage" innerclass="inner" />
 			<roundcube:button command="image-rotate" type="link"
 				class="button rotate disabled" classAct="button rotate"
 				label="rotate" title="rotateimage" innerclass="inner" />
 		</div>
 		<a href="#" class="button icon tools" onclick="$(this).attr('title', $(this).data('label-' + ($('#image-tools').toggleClass('open').is('.open') ? 'hide' : 'show')))"
 			data-label-show="<roundcube:label name="showtools" />" data-label-hide="<roundcube:label name="hidetools" />" title="<roundcube:label name="showtools" />">
 			<span class="inner"><roundcube:label name="showtools" /></span>
 		</a>
 	</div>
 <roundcube:endif />
 
-<script>
-window.rcmail && rcmail.addEventListener('init', function(evt) {
-    if (rcmail.gui_objects.attachmentframe) {
-        rcmail.gui_objects.messagepartframe = rcmail.gui_objects.attachmentframe;
-        rcmail.enable_command('image-scale', 'image-rotate', !!/^image\//.test(rcmail.env.mimetype));
-        rcmail.register_command('print-attachment', function() {
-            var frame = rcmail.get_frame_window(rcmail.gui_objects.attachmentframe.id);
-            if (frame) frame.print();
-        }, true);
-    }
-
-    if (rcmail.env.attachment_download_url) {
-        rcmail.register_command('download-attachment', function() {
-            rcmail.location_href(rcmail.env.attachment_download_url, window);
-        }, true);
-    }
-});
-</script>
-
 <roundcube:include file="includes/footer.html" />
diff --git a/plugins/libkolab/skins/larry/templates/attachment.html b/plugins/libkolab/skins/larry/templates/attachment.html
index 664d5f7c..4acc2e7b 100644
--- a/plugins/libkolab/skins/larry/templates/attachment.html
+++ b/plugins/libkolab/skins/larry/templates/attachment.html
@@ -1,82 +1,65 @@
 <roundcube:object name="doctype" value="html5" />
 <html>
 <head>
 <title><roundcube:object name="pagetitle" /></title>
 <roundcube:include file="/includes/links.html" />
 </head>
 <body class="extwin libkolab attachmentwin">
 
 <div id="header">
 <div id="topline" role="banner" aria-labelledby="aria-label-topnav">
 	<div class="topleft">
 		<roundcube:container name="topline-left" id="topline-left" />
 	</div>
 	<roundcube:container name="topline-center" id="topline-center" />
 	<div class="topright">
 		<roundcube:container name="topline-right" id="topline-right" />
 		<roundcube:button name="close" type="link" label="close" class="closelink" onclick="self.close()" />
 	</div>
 </div>
 </div>
 
 <div id="mainscreen">
 
 <h1 class="voice"><roundcube:label name="attachment" />: <roundcube:var name="env:filename" /></h1>
 
 <h2 id="aria-label-toolbar" class="voice"><roundcube:label name="arialabeltoolbar" /></h2>
 <div id="attachmenttoolbar" class="toolbar fullwidth" role="toolbar" aria-labelledby="aria-label-toolbar">
 	<roundcube:button command="download-attachment" type="link" class="button download disabled" classAct="button download" classSel="button download pressed" label="download" title="download" />
 	<roundcube:button command="print-attachment" type="link" class="button print disabled" classAct="button print" classSel="button print pressed" label="print" title="print" />
 	<roundcube:container name="toolbar" id="messagetoolbar" />
 </div>
 
 <div id="mainscreencontent">
 
 	<div id="partheader" class="uibox listbox" role="contentinfo" aria-labelledby="aria-label-contentinfo">
 		<h2 class="boxtitle" id="aria-label-contentinfo"><roundcube:label name="properties" /></h2>
 		<div class="scroller">
 			<roundcube:object name="plugin.attachmentcontrols" class="listing" />
 		</div>
 	</div>
 
 	<div id="attachmentcontainer" class="uibox" role="main" aria-labelledby="aria-label-messagepart">
 		<h2 id="aria-label-messagepart" class="voice"><roundcube:label name="arialabelattachmentpreview" /></h2>
 		<div class="iframebox">
 		<roundcube:object name="plugin.attachmentframe" id="attachmentframe" frameborder="0" title="arialabelattachmentpreview" />
 		</div>
 	</div>
 
 </div>
 
 </div>
 
 <script type="text/javascript">
 
 $(document).ready(function() {
     if (window.rcube_splitter) {
         new rcube_splitter({ id:'mailpartsplitterv', p1:'#partheader', p2:'#attachmentcontainer',
             orientation:'v', relative:true, start:226, min:150, size:12}).init();
     }
 });
 
-window.rcmail && rcmail.addEventListener('init', function(evt) {
-    if (rcmail.gui_objects.attachmentframe) {
-        rcmail.gui_objects.messagepartframe = rcmail.gui_objects.attachmentframe;
-        rcmail.enable_command('image-scale', 'image-rotate', !!/^image\//.test(rcmail.env.mimetype));
-        rcmail.register_command('print-attachment', function() {
-            var frame = rcmail.get_frame_window(rcmail.gui_objects.attachmentframe.id);
-            if (frame) frame.print();
-        }, true);
-    }
-
-    if (rcmail.env.attachment_download_url) {
-        rcmail.register_command('download-attachment', function() {
-            rcmail.location_href(rcmail.env.attachment_download_url, window);
-        }, true);
-    }
-});
-
 </script>
 
 </body>
 </html>
diff --git a/plugins/tasklist/tasklist_ui.php b/plugins/tasklist/tasklist_ui.php
index 48b0c425..a8bfb170 100644
--- a/plugins/tasklist/tasklist_ui.php
+++ b/plugins/tasklist/tasklist_ui.php
@@ -1,614 +1,609 @@
 <?php
 /**
  * User Interface class for the Tasklist plugin
  *
  * @version @package_version@
  * @author Thomas Bruederli <bruederli@kolabsys.com>
  *
  * Copyright (C) 2012-2015, Kolab Systems AG <contact@kolabsys.com>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Affero General Public License as
  * published by the Free Software Foundation, either version 3 of the
  * License, or (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU Affero General Public License for more details.
  *
  * You should have received a copy of the GNU Affero General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
 
 class tasklist_ui
 {
     private $rc;
     private $plugin;
     private $ready = false;
     private $gui_objects = array();
 
     function __construct($plugin)
     {
         $this->plugin = $plugin;
         $this->rc     = $plugin->rc;
     }
 
     /**
      * Calendar UI initialization and requests handlers
      */
     public function init()
     {
         if ($this->ready) {
             return;
         }
 
         // add taskbar button
         $this->plugin->add_button(array(
             'command'    => 'tasks',
             'class'      => 'button-tasklist',
             'classsel'   => 'button-tasklist button-selected',
             'innerclass' => 'button-inner',
             'label'      => 'tasklist.navtitle',
             'type'       => 'link'
         ), 'taskbar');
 
         $this->plugin->include_stylesheet($this->plugin->local_skin_path() . '/tasklist.css');
 
         if ($this->rc->task == 'mail' || $this->rc->task == 'tasks') {
             $this->plugin->include_script('tasklist_base.js');
 
             // copy config to client
             $this->rc->output->set_env('tasklist_settings', $this->load_settings());
 
             // initialize attendees autocompletion
             $this->rc->autocomplete_init();
         }
 
         $this->ready = true;
     }
 
     /**
      *
      */
     function load_settings()
     {
         $settings = array();
 
         $settings['invite_shared'] = (int)$this->rc->config->get('calendar_allow_invite_shared', 0);
         $settings['itip_notify']   = (int)$this->rc->config->get('calendar_itip_send_option', 3);
         $settings['sort_col']      = $this->rc->config->get('tasklist_sort_col', '');
         $settings['sort_order']    = $this->rc->config->get('tasklist_sort_order', 'asc');
 
         // get user identity to create default attendee
         foreach ($this->rc->user->list_emails() as $rec) {
             if (!$identity)
                 $identity = $rec;
 
             $identity['emails'][] = $rec['email'];
             $settings['identities'][$rec['identity_id']] = $rec['email'];
         }
 
         $identity['emails'][] = $this->rc->user->get_username();
         $settings['identity'] = array(
             'name'   => $identity['name'],
             'email'  => strtolower($identity['email']),
             'emails' => ';' . strtolower(join(';', $identity['emails']))
         );
 
         if ($list = rcube_utils::get_input_value('_list', rcube_utils::INPUT_GPC)) {
             $settings['selected_list'] = $list;
         }
         if ($list && ($id = rcube_utils::get_input_value('_id', rcube_utils::INPUT_GPC))) {
             $settings['selected_id'] = $id;
 
             // check if the referenced task is completed
             $task = $this->plugin->driver->get_task(array('id' => $id, 'list' => $list));
             if ($task && $this->plugin->driver->is_complete($task)) {
                 $settings['selected_filter'] = 'complete';
             }
         }
         else if ($filter = rcube_utils::get_input_value('_filter', rcube_utils::INPUT_GPC)) {
             $settings['selected_filter'] = $filter;
         }
 
         return $settings;
     }
 
     /**
      * Render a HTML select box for user identity selection
      */
     function identity_select($attrib = array())
     {
         $attrib['name'] = 'identity';
         $select         = new html_select($attrib);
         $identities     = $this->rc->user->list_emails();
 
         foreach ($identities as $ident) {
             $select->add(format_email_recipient($ident['email'], $ident['name']), $ident['identity_id']);
         }
 
         return $select->show(null);
     }
 
     /**
     * Register handler methods for the template engine
     */
     public function init_templates()
     {
         $this->plugin->register_handler('plugin.tasklists', array($this, 'tasklists'));
         $this->plugin->register_handler('plugin.tasklist_select', array($this, 'tasklist_select'));
         $this->plugin->register_handler('plugin.status_select', array($this, 'status_select'));
         $this->plugin->register_handler('plugin.searchform', array($this->rc->output, 'search_form'));
         $this->plugin->register_handler('plugin.quickaddform', array($this, 'quickadd_form'));
         $this->plugin->register_handler('plugin.tasks', array($this, 'tasks_resultview'));
         $this->plugin->register_handler('plugin.tags_editline', array($this, 'tags_editline'));
         $this->plugin->register_handler('plugin.alarm_select', array($this, 'alarm_select'));
         $this->plugin->register_handler('plugin.recurrence_form', array($this->plugin->lib, 'recurrence_form'));
         $this->plugin->register_handler('plugin.attachments_form', array($this, 'attachments_form'));
         $this->plugin->register_handler('plugin.attachments_list', array($this, 'attachments_list'));
         $this->plugin->register_handler('plugin.filedroparea', array($this, 'file_drop_area'));
         $this->plugin->register_handler('plugin.attendees_list', array($this, 'attendees_list'));
         $this->plugin->register_handler('plugin.attendees_form', array($this, 'attendees_form'));
         $this->plugin->register_handler('plugin.identity_select', array($this, 'identity_select'));
         $this->plugin->register_handler('plugin.edit_attendees_notify', array($this, 'edit_attendees_notify'));
         $this->plugin->register_handler('plugin.task_rsvp_buttons', array($this->plugin->itip, 'itip_rsvp_buttons'));
         $this->plugin->register_handler('plugin.object_changelog_table', array('libkolab', 'object_changelog_table'));
         $this->plugin->register_handler('plugin.tasks_export_form', array($this, 'tasks_export_form'));
         $this->plugin->register_handler('plugin.tasks_import_form', array($this, 'tasks_import_form'));
 
         $this->plugin->include_script('tasklist.js');
         $this->rc->output->include_script('treelist.js');
-
-        // include kolab folderlist widget if available
-        if (in_array('libkolab', $this->plugin->api->loaded_plugins())) {
-            $this->plugin->api->include_script('libkolab/js/folderlist.js');
-            $this->plugin->api->include_script('libkolab/js/audittrail.js');
-        }
+        $this->plugin->api->include_script('libkolab/libkolab.js');
     }
 
     /**
      *
      */
     public function tasklists($attrib = array())
     {
         $tree = true;
         $jsenv = array();
         $lists = $this->plugin->driver->get_lists(0, $tree);
 
         if (empty($attrib['id'])) {
             $attrib['id'] = 'rcmtasklistslist';
         }
 
         // walk folder tree
         if (is_object($tree)) {
             $html = $this->list_tree_html($tree, $lists, $jsenv, $attrib);
         }
         else {
             // fall-back to flat folder listing
             $attrib['class'] .= ' flat';
 
             $html = '';
             foreach ((array)$lists as $id => $prop) {
                 if ($attrib['activeonly'] && !$prop['active'])
                   continue;
 
                 $html .= html::tag('li', array(
                         'id' => 'rcmlitasklist' . rcube_utils::html_identifier($id),
                         'class' => $prop['group'],
                     ),
                     $this->tasklist_list_item($id, $prop, $jsenv, $attrib['activeonly'])
                 );
             }
         }
 
         $this->rc->output->set_env('source', rcube_utils::get_input_value('source', rcube_utils::INPUT_GET));
         $this->rc->output->set_env('tasklists', $jsenv);
         $this->register_gui_object('tasklistslist', $attrib['id']);
 
         return html::tag('ul', $attrib, $html, html::$common_attrib);
     }
 
     /**
      * Return html for a structured list <ul> for the folder tree
      */
     public function list_tree_html($node, $data, &$jsenv, $attrib)
     {
         $out = '';
         foreach ($node->children as $folder) {
             $id = $folder->id;
             $prop = $data[$id];
             $is_collapsed = false; // TODO: determine this somehow?
 
             $content = $this->tasklist_list_item($id, $prop, $jsenv, $attrib['activeonly']);
 
             if (!empty($folder->children)) {
                 $content .= html::tag('ul', array('style' => ($is_collapsed ? "display:none;" : null)),
                     $this->list_tree_html($folder, $data, $jsenv, $attrib));
             }
 
             if (strlen($content)) {
                 $out .= html::tag('li', array(
                       'id' => 'rcmlitasklist' . rcube_utils::html_identifier($id),
                       'class' => $prop['group'] . ($prop['virtual'] ? ' virtual' : ''),
                     ),
                     $content);
             }
         }
 
         return $out;
     }
 
     /**
      * Helper method to build a tasklist item (HTML content and js data)
      */
     public function tasklist_list_item($id, $prop, &$jsenv, $activeonly = false)
     {
         // enrich list properties with settings from the driver
         if (!$prop['virtual']) {
             unset($prop['user_id']);
             $prop['alarms']      = $this->plugin->driver->alarms;
             $prop['undelete']    = $this->plugin->driver->undelete;
             $prop['sortable']    = $this->plugin->driver->sortable;
             $prop['attachments'] = $this->plugin->driver->attachments;
             $prop['attendees']   = $this->plugin->driver->attendees;
             $prop['caldavurl']   = $this->plugin->driver->tasklist_caldav_url($prop);
             $jsenv[$id] = $prop;
         }
 
         $classes = array('tasklist');
         $title = $prop['title'] ?: ($prop['name'] != $prop['listname'] || strlen($prop['name']) > 25 ?
           html_entity_decode($prop['name'], ENT_COMPAT, RCUBE_CHARSET) : '');
 
         if ($prop['virtual'])
             $classes[] = 'virtual';
         else if (!$prop['editable'])
             $classes[] = 'readonly';
         if ($prop['subscribed'])
             $classes[] = 'subscribed';
         if ($prop['class'])
             $classes[] = $prop['class'];
 
         if (!$activeonly || $prop['active']) {
             $label_id = 'tl:' . $id;
             return html::div(join(' ', $classes),
                 html::a(array('class' => 'listname', 'title' => $title, 'href' => '#', 'id' => $label_id), $prop['listname'] ?: $prop['name']) .
                   ($prop['virtual'] ? '' :
                       html::tag('input', array('type' => 'checkbox', 'name' => '_list[]', 'value' => $id, 'checked' => $prop['active'], 'aria-labelledby' => $label_id)) .
                       html::span('actions', 
                           ($prop['removable'] ? html::a(array('href' => '#', 'class' => 'remove', 'title' => $this->plugin->gettext('removelist')), ' ') : '') .
                           html::a(array('href' => '#', 'class' => 'quickview', 'title' => $this->plugin->gettext('focusview'), 'role' => 'checkbox', 'aria-checked' => 'false'), ' ') .
                           (isset($prop['subscribed']) ? html::a(array('href' => '#', 'class' => 'subscribed', 'title' => $this->plugin->gettext('tasklistsubscribe'), 'role' => 'checkbox', 'aria-checked' => $prop['subscribed'] ? 'true' : 'false'), ' ') : '')
                       )
                 )
             );
         }
 
         return '';
     }
 
     /**
      * Render HTML form for task status selector
      */
     function status_select($attrib = array())
     {
         $attrib['name'] = 'status';
         $select = new html_select($attrib);
         $select->add('---', '');
         $select->add($this->plugin->gettext('status-needs-action'), 'NEEDS-ACTION');
         $select->add($this->plugin->gettext('status-in-process'),   'IN-PROCESS');
         $select->add($this->plugin->gettext('status-completed'),    'COMPLETED');
         $select->add($this->plugin->gettext('status-cancelled'),    'CANCELLED');
 
         return $select->show(null);
     }
 
     /**
      * Render a HTML select box for list selection
      */
     function tasklist_select($attrib = array())
     {
         if (empty($attrib['name'])) {
             $attrib['name'] = 'list';
         }
 
         $attrib['is_escaped'] = true;
         $select = new html_select($attrib);
         $default = null;
 
         foreach ((array) $attrib['extra'] as $id => $name) {
             $select->add($name, $id);
         }
 
         foreach ((array)$this->plugin->driver->get_lists() as $id => $prop) {
             if ($prop['editable'] || strpos($prop['rights'], 'i') !== false) {
                 $select->add($prop['name'], $id);
                 if (!$default || $prop['default'])
                     $default = $id;
             }
         }
 
         return $select->show($default);
     }
 
     function tasklist_editform($action, $list = array())
     {
         $this->action = $action;
         $this->list   = $list;
         $this->rc->output->add_handler('tasklistform', array($this, 'tasklistform'));
         $this->rc->output->send('tasklist.listform');
     }
 
     function tasklistform($attrib)
     {
         $fields = array(
             'name' => array(
                 'id'    => 'taskedit-tasklistname',
                 'label' => $this->plugin->gettext('listname'),
                 'value' => html::tag('input', array('id' => 'taskedit-tasklistname', 'name' => 'name', 'type' => 'text', 'class' => 'text', 'size' => 40)),
             ),
 /*
             'color' => array(
                 'id'    => 'taskedit-color',
                 'label' => $this->plugin->gettext('color'),
                 'value' => html::tag('input', array('id' => 'taskedit-color', 'name' => 'color', 'type' => 'text', 'class' => 'text colorpicker', 'size' => 6)),
             ),
 */
             'showalarms' => array(
                 'id'    => 'taskedit-showalarms',
                 'label' => $this->plugin->gettext('showalarms'),
                 'value' => html::tag('input', array('id' => 'taskedit-showalarms', 'name' => 'color', 'type' => 'checkbox')),
             ),
         );
 
         return html::tag('form', $attrib + array('action' => "#", 'method' => "post", 'id' => 'tasklisteditform'),
             $this->plugin->driver->tasklist_edit_form($this->action, $this->list, $fields)
         );
     }
 
     /**
      * Render HTML form for alarm configuration
      */
     function alarm_select($attrib = array())
     {
         $attrib['_type'] = 'task';
         return $this->plugin->lib->alarm_select($attrib, $this->plugin->driver->alarm_types, $this->plugin->driver->alarm_absolute);
     }
 
     /**
      *
      */
     function quickadd_form($attrib)
     {
         $attrib += array('action' => $this->rc->url('add'), 'method' => 'post', 'id' => 'quickaddform');
 
         $label = html::label(array('for' => 'quickaddinput', 'class' => 'voice'), $this->plugin->gettext('quickaddinput'));
         $input = new html_inputfield(array('name' => 'text', 'id' => 'quickaddinput'));
         $button = html::tag('input', array('type' => 'submit', 'value' => '+', 'title' => $this->plugin->gettext('createtask'), 'class' => 'button mainaction'));
 
         $this->register_gui_object('quickaddform', $attrib['id']);
         return html::tag('form', $attrib, $label . $input->show() . $button);
     }
 
     /**
      * The result view
      */
     function tasks_resultview($attrib)
     {
         $attrib += array('id' => 'rcmtaskslist');
 
         $this->register_gui_object('resultlist', $attrib['id']);
 
         unset($attrib['name']);
         return html::tag('ul', $attrib, '');
     }
 
     /**
      * Interactive UI element to add/remove tags
      */
     function tags_editline($attrib)
     {
         $attrib += array('id' => 'rcmtasktagsedit');
         $this->register_gui_object('edittagline', $attrib['id']);
 
         $input = new html_inputfield(array('name' => 'tags[]', 'class' => 'tag', 'size' => $attrib['size'], 'tabindex' => $attrib['tabindex']));
         unset($attrib['tabindex']);
         return html::div($attrib, $input->show(''));
     }
 
     /**
      * Generate HTML element for attachments list
      */
     function attachments_list($attrib = array())
     {
         if (!$attrib['id']) {
             $attrib['id'] = 'rcmtaskattachmentlist';
         }
 
         $this->register_gui_object('attachmentlist', $attrib['id']);
 
         return html::tag('ul', $attrib, '', html::$common_attrib);
     }
 
     /**
      * Generate the form for event attachments upload
      */
     function attachments_form($attrib = array())
     {
         // add ID if not given
         if (!$attrib['id']) {
             $attrib['id'] = 'rcmtaskuploadform';
         }
 
         return $this->rc->upload_form($attrib, 'uploadform', 'upload-file', array('multiple' => true));
     }
 
     /**
      * Register UI object for HTML5 drag & drop file upload
      */
     function file_drop_area($attrib = array())
     {
         if ($attrib['id']) {
             $this->register_gui_object('filedrop', $attrib['id']);
             $this->rc->output->set_env('filedrop', array('action' => 'upload', 'fieldname' => '_attachments'));
         }
     }
 
     /**
      *
      */
     function attendees_list($attrib = array())
     {
         // add "noreply" checkbox to attendees table only
         $invitations = strpos($attrib['id'], 'attend') !== false;
 
         $invite = new html_checkbox(array('value' => 1, 'id' => 'edit-attendees-invite'));
         $table  = new html_table(array('cols' => 4 + intval($invitations), 'border' => 0, 'cellpadding' => 0, 'class' => 'rectable'));
 
 //      $table->add_header('role', $this->plugin->gettext('role'));
         $table->add_header('name', $this->plugin->gettext($attrib['coltitle'] ?: 'attendee'));
         $table->add_header('confirmstate', $this->plugin->gettext('confirmstate'));
         if ($invitations) {
             $table->add_header(array('class' => 'invite', 'title' => $this->plugin->gettext('sendinvitations')),
                 $invite->show(1) . html::label('edit-attendees-invite', $this->plugin->gettext('sendinvitations')));
         }
         $table->add_header('options', '');
 
         // hide invite column if disabled by config
         $itip_notify = (int)$this->rc->config->get('calendar_itip_send_option', 3);
         if ($invitations && !($itip_notify & 2)) {
             $css = sprintf('#%s td.invite, #%s th.invite { display:none !important }', $attrib['id'], $attrib['id']);
             $this->rc->output->add_footer(html::tag('style', array('type' => 'text/css'), $css));
         }
 
         return $table->show($attrib);
     }
 
     /**
      *
      */
     function attendees_form($attrib = array())
     {
         $input    = new html_inputfield(array('name' => 'participant', 'id' => 'edit-attendee-name', 'size' => 30));
         $textarea = new html_textarea(array('name' => 'comment', 'id' => 'edit-attendees-comment',
             'rows' => 4, 'cols' => 55, 'title' => $this->plugin->gettext('itipcommenttitle')));
 
         return html::div($attrib,
             html::div(null, $input->show() . " " .
                 html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-add', 'value' => $this->plugin->gettext('addattendee')))
                 // . " " . html::tag('input', array('type' => 'button', 'class' => 'button', 'id' => 'edit-attendee-schedule', 'value' => $this->plugin->gettext('scheduletime').'...'))
                 ) .
             html::p('attendees-commentbox', html::label(null, $this->plugin->gettext('itipcomment') . $textarea->show()))
         );
     }
 
     /**
      *
      */
     function edit_attendees_notify($attrib = array())
     {
         $checkbox = new html_checkbox(array('name' => '_notify', 'id' => 'edit-attendees-donotify', 'value' => 1));
         return html::div($attrib, html::label(null, $checkbox->show(1) . ' ' . $this->plugin->gettext('sendnotifications')));
     }
 
     /**
      * Form for uploading and importing tasks
      */
     function tasks_import_form($attrib = array())
     {
         if (!$attrib['id']) {
             $attrib['id'] = 'rcmImportForm';
         }
 
         // Get max filesize, enable upload progress bar
         $max_filesize = $this->rc->upload_init();
         $accept       = '.ics, text/calendar, text/x-vcalendar, application/ics';
         if (class_exists('ZipArchive', false)) {
             $accept .= ', .zip, application/zip';
         }
 
         $input = new html_inputfield(array(
                 'type'   => 'file',
                 'name'   => '_data',
                 'size'   => $attrib['uploadfieldsize'],
                 'accept' => $accept
         ));
 
         $html = html::div('form-section form-group row',
             html::label(array('class' => 'col-sm-4 col-form-label', 'for' => 'importfile'), rcube::Q($this->rc->gettext('importfromfile')))
             . html::div('col-sm-8', $input->show()
                 . html::div('hint', $this->rc->gettext(array('id' => 'importfile', 'name' => 'maxuploadsize', 'vars' => array('size' => $max_filesize)))))
         );
 
         $html .= html::div('form-section form-group row',
             html::label(array('for' => 'task-import-list', 'class' => 'col-sm-4 col-form-label'), $this->plugin->gettext('list'))
             . html::div('col-sm-8', $this->tasklist_select(array('name' => 'source', 'id' => 'task-import-list', 'editable' => true)))
         );
 
         $this->rc->output->add_gui_object('importform', $attrib['id']);
         $this->rc->output->add_label('import', 'importerror');
 
         return html::tag('p', null, $this->plugin->gettext('importtext'))
             .html::tag('form', array(
                 'action'  => $this->rc->url(array('task' => 'tasklist', 'action' => 'import')),
                 'method'  => 'post',
                 'enctype' => 'multipart/form-data',
                 'id'      => $attrib['id'],
             ),
             $html
         );
     }
 
     /**
      * Form to select options for exporting tasks
      */
     function tasks_export_form($attrib = array())
     {
         if (!$attrib['id']) {
             $attrib['id'] = 'rcmTaskExportForm';
         }
 
         $html .= html::div('form-section form-group row',
             html::label(array('for' => 'task-export-list', 'class' => 'col-sm-4 col-form-label'), $this->plugin->gettext('list'))
             . html::div('col-sm-8', $this->tasklist_select(array(
                         'name'  => 'source',
                         'id'    => 'task-export-list',
                         'extra' => array('' => '- ' . $this->plugin->gettext('currentview') . ' -'),
                 )))
         );
 
         $checkbox = new html_checkbox(array('name' => 'attachments', 'id' => 'task-export-attachments', 'value' => 1, 'class' => 'form-check-input'));
         $html .= html::div('form-section form-group row form-check',
             html::label(array('for' => 'task-export-attachments', 'class' => 'col-sm-4 col-form-label'), $this->plugin->gettext('exportattachments'))
             . html::div('col-sm-8', $checkbox->show(1))
         );
 
         $this->register_gui_object('exportform', $attrib['id']);
 
         return html::tag('form', array(
                 'action' => $this->rc->url(array('task' => 'tasklist', 'action' => 'export')),
                 'method' => 'post', 'id' => $attrib['id']
             ),
             $html
         );
     }
 
     /**
      * Wrapper for rcube_output_html::add_gui_object()
      */
     function register_gui_object($name, $id)
     {
         $this->gui_objects[$name] = $id;
         $this->rc->output->add_gui_object($name, $id);
     }
 
     /**
      * Getter for registered gui objects.
      * (for manual registration when loading the inline UI)
      */
     function get_gui_objects()
     {
         return $this->gui_objects;
     }
 }