Add/Edit of Tasks jQuery-Error
Since jQuery of Roundcube was updated there is an error when you try to add or edit a task:
Uncaught Error: no such method 'select' for tabs widget instance
This can be fixed by changing line 1052 in tasklisttasklist.js from:
$('#taskedit').tabs('select', 0);
to:
$('#taskedit').tabs('option', {'active': 0});
The select method was dropped by jQuery UI some versions ago