When I open the "Files" tab in Roundcube, select a text file and double-click it, a separate window appears showing the editor control with my text file in it, but I cannot edit the text file. I seems to be read-only. Google Chrome's console contains the following error:

treelist.js:1 Uncaught TypeError: Cannot read property 'top' of undefined
at scroll_to_node (treelist.js:1)
at rcube_treelist_widget.select (treelist.js:1)
at files_api.folder_list_response (kolab_files.js:2)
at Object.success (files_api.js:105)
at j (jquery.min.js:34)
at Object.fireWith [as resolveWith] (jquery.min.js:34)
at x (jquery.min.js:36)
at XMLHttpRequest.<anonymous> (jquery.min.js:36)
scroll_to_node @ treelist.js:1
select @ treelist.js:1
folder_list_response @ kolab_files.js:2
success @ files_api.js:105
j @ jquery.min.js:34
fireWith @ jquery.min.js:34
x @ jquery.min.js:36
(anonymous) @ jquery.min.js:36

My chwala version: chwala-0.5-12.1.el7.kolab_16.noarch
I don't know exactly whether this is a chwala issue, so please let me know, if you need the version of some other package.