This seems like a problem with the new version of the vbulletin software, so I don't know if there's any easy fix from our end, but maybe you can find something more easily than I can.

The bug: when I use the multiquote function to select multiple quotes in a thread, and then hit "go advanced" in the quick reply box after loading the quotes into the reply, the quotes do not get deselected after I submit the reply. If I go to reply to the thread again, those quotes remain selected.