After upgrading from 6.3 to 6.4.12 very often, JIRA Dialogs and comments boxes do not close, both after transitions and after making comments, the rotating gif just rotates.. Pressing ESC does close the Dialog box and the transition/comment or whatever has been done.
Also, after filedrop in JIRA, a manual refresh is needed for the file to "show up" in the GUI.
This is seen very often in Chrome, but also reported for Firefox. All plugins are updated. This nothing shown in the logs.