These captions are in fact empty but for convenience another language caption is displayed between <>. Sort on the column to see all empty caption on top of the list.
I see. Sorting does not show these captions however. They do not appear in the Batch Replace list at all. I guess that makes sense if they're empty. Still, a way to find and edit them would be nice.
Right now I see no other way then using CTRL-F (look for "<" or ">") to find them.
Thanks for your reply!