Well I updated and everything still seems to work.
The plugin I am talking about is not one of those calibre supported ones. I don't think we can talk about it on this board, but you know, the ones I need for backing up and liberating my kindle books.

. I am still using an older version as I don't want to mess with something that works. No clue if I can figure this one out all over again. But it seems to still operate as is.
The other plugins I got, ones that came through calibre like the goodreads, or resize cover etc seem to also work. I haven't tried all of them yet, but so far so good.
I just discovered virtual libraries and now I am spending even more time sorting and cataloging the books I don't seem to have time to read.

And the cover view is really great. Makes it also easier to add a cover to those I haven't done yet. I still have a lot of cleaning up to do.
But after getting rid of a gazillion bad romance freebies, I am really more careful about what I get. And backlist stuff will always have priority over some first published unknown indy stuff. At least the backlist stuff is full novels and not just chunks.
Goal today is finishing the book I am reading now and hopefully find another good one right after.