Where are menu history entries stored/how do I clear them?
 

I find it easier to clean up my collection by sorting into multiple libraries by author or category. I have many such libraries but now my context menus are getting cluttered by history from copying books between libraries and switching libraries. I've searched for where this information is stored and I did find a history file in the calibre configuration directory but deleting it seems to not make any difference. Where is this information stored? How do I clear it?

look in gui.json

Thanks, that worked.