I've noticed that sometimes Picard does not see see filesystem updates that occur outside of Picard.  I'm assuming this is from the filesystem change monitoring either missing some update notifications, or just that not working on certain filesystems due to missing support.  That is not the issue at hand.

The issue is that once Picard has missed some filesystem changes for whatever reason, there doesn't seem to be any way (short of restarting Picard) to get it to update the file listings.  Even clicking on now non-existent files/dirs and trying to do operations on them doesn't cause it to realize they aren't there anymore or that new files have appeared in them.

I think there needs to be an option in the file browser pane context menu to "Refresh" (selected dirs/files) and "Refresh All" (all expanded dirs/files).  In addition, it would be good if picard re-scanned any directory that is actively being worked in within picard whenever a new operation is initiated in that directory (select, expand/collapse, scan, process, save, etc).