Sorry, no change. The problem persists.
A "Save" in "Source Libraries" is *always* eating three of my libraries. I have now 26 libraries an tried different combinations to get at least the two libraries I am interested. For this I have to save 5 libraries and including 3 copies (= in total 4) of on library I am interested.
I checked if it has to do with an alphabetically listing or with the time of the generation of the libraries. I didn't find any pattern.
The only thing I can think off is still some weird interference with the "View Manager" plugin. In all my tests I have worked without "View Manager", but still I always get when I click on ""Extract a Fresh Copy…" the message that "View Manager" is my target library.
I remember that I had one a fatal error with "View Manager" as a renamed or copied a library to another place. Or did I rename a view in "View Manager" - I can't remember exactly, but thinking now it was probably renaming a view. "View Manager" had enabled "Last View Used" and this had the consequences that I could not start Calibre as it crashed down always trying the appropriate view. This was exactly the time when I renamed my view with 00, 01 and 02 in order have it alphabetically listed and linked with a shortcut command via the OSX panel. so I could change rapidly between the most important views.
I think that getting these weird numbers 00,01 and 02 used with "View Manager" *and* getting this strange reference that "View Manager" is my target library can't be an accident.
So far my newbie-conclusions. Any ideas what could I try next?