diff --git a/plugins/kolab_notes/kolab_notes_ui.php b/plugins/kolab_notes/kolab_notes_ui.php
index 99cce46a..f180f50a 100644
--- a/plugins/kolab_notes/kolab_notes_ui.php
+++ b/plugins/kolab_notes/kolab_notes_ui.php
@@ -1,439 +1,440 @@
 <?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',
         ), 'taskbar');
 
         $this->plugin->include_stylesheet($this->plugin->local_skin_path() . '/notes.css');
 
         $this->plugin->register_action('print', array($this, 'print_template'));
         $this->plugin->register_action('folder-acl', array($this, 'folder_acl'));
 
         $this->ready = true;
   }
 
     /**
     * Register handler methods for the template engine
     */
     public function init_templates()
     {
         $this->plugin->register_handler('plugin.tagslist', array($this, 'tagslist'));
         $this->plugin->register_handler('plugin.notebooks', array($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');
 
         jqueryui::tagedit();
 
         // 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');
         }
 
         // load config options and user prefs relevant for the UI
         $settings = array(
             'sort_col' => $this->rc->config->get('kolab_notes_sort_col', 'changed'),
             'print_template' => $this->rc->url('print'),
         );
 
         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;
         }
 
         $lang_codes = array($_SESSION['language']);
+        $assets_dir = $this->rc->config->get('assets_dir') ?: INSTALL_PATH;
 
         if ($pos = strpos($_SESSION['language'], '_')) {
             $lang_codes[] = substr($_SESSION['language'], 0, $pos);
         }
 
         foreach ($lang_codes as $code) {
-            if (file_exists(INSTALL_PATH . "program/js/tinymce/langs/$code.js")) {
+            if (file_exists("$assets_dir/program/js/tinymce/langs/$code.js")) {
                 $lang = $code;
                 break;
             }
         }
 
         if (empty($lang)) {
             $lang = 'en';
         }
 
         $settings['editor'] = array(
             'lang'       => $lang,
             'spellcheck' => intval($this->rc->config->get('enable_spellcheck')),
             'spelldict'  => intval($this->rc->config->get('spellcheck_dictionary'))
         );
 
         $this->rc->output->set_env('kolab_notes_settings', $settings);
 
         $this->rc->output->add_label('save','cancel','delete','close');
     }
 
     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('ul', $attrib, '', html::$common_attrib);
     }
 
     public function tagslist($attrib)
     {
         $attrib += array('id' => 'rcmkolabnotestagslist');
         $this->rc->output->add_gui_object('notestagslist', $attrib['id']);
         return html::tag('ul', $attrib, '', html::$common_attrib);
     }
 
     public function editform($attrib)
     {
         $attrib += array('action' => '#', 'id' => 'rcmkolabnoteseditform');
 
         $this->rc->output->add_gui_object('noteseditform', $attrib['id']);
         $this->rc->output->include_script('tinymce/tinymce.min.js');
 
         $textarea = new html_textarea(array('name' => 'content', 'id' => 'notecontent', 'cols' => 60, 'rows' => 20, 'tabindex' => 0));
         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', 'size' => 60, 'tabindex' => 0));
 
         $html = $summary->show();
         $html .= html::div(array('class' => 'tagline tagedit', 'style' => 'display:none'), '&nbsp;');
         $html .= html::div(array('class' => 'dates', 'style' => 'display:none'),
             html::label(array(), $this->plugin->gettext('created')) .
             html::span('notecreated', '') .
             html::label(array(), $this->plugin->gettext('changed')) .
             html::span('notechanged', '')
         );
 
         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 edit for notes lists (folders)
      */
     public function list_editform($action, $list, $folder)
     {
         if (is_object($folder)) {
             $folder_name = $folder->name; // UTF7
         }
         else {
             $folder_name = '';
         }
 
         $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' => $input_name->show($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 ($action != 'form-new') {
             $form['sharing'] = array(
                 'name'    => rcube::Q($this->plugin->gettext('tabsharing')),
                 'content' => html::tag('iframe', array(
                     'src' => $this->rc->url(array('_action' => 'folder-acl', '_folder' => $folder_name, 'framed' => 1)),
                     'width' => '100%',
                     'height' => 280,
                     'border' => 0,
                     'style' => 'border:0'),
                 '')
             );
         }
 
         $form_html = '';
         if (is_array($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'])) {
                 $table = new html_table(array('cols' => 2));
                 foreach ($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', array('action' => "#", 'method' => "post", 'id' => "noteslistpropform"), $form_html);
     }
 
     /**
      * Handler to render ACL form for a notes folder
      */
     public function folder_acl()
     {
         $this->plugin->require_plugin('acl');
         $this->rc->output->add_handler('folderacl', array($this, 'folder_acl_form'));
         $this->rc->output->send('kolab_notes.kolabacl');
     }
 
     /**
      * Handler for ACL form template object
      */
     public function folder_acl_form()
     {
         $folder = rcube_utils::get_input_value('_folder', rcube_utils::INPUT_GPC);
 
         if (strlen($folder)) {
             $storage = $this->rc->get_storage();
             $options = $storage->folder_info($folder);
 
             // get sharing UI from acl plugin
             $acl = $this->rc->plugins->exec_hook('folder_form',
                 array('form' => array(), 'options' => $options, 'name' => $folder));
         }
 
         return $acl['form']['sharing']['content'] ?: html::div('hint', $this->plugin->gettext('aclnorights'));
     }
 
     /**
      * Render the template for printing with placeholders
      */
     public function print_template()
     {
         header('Content-Type: text/html; charset=' . RCUBE_CHARSET);
         $this->rc->output->reset(true);
         echo $this->rc->output->parse('kolab_notes.print', false, false);
         exit;
     }
 
 }