When I am in the Library module and I want to view the image in the fit mode the programm shows the image in 100% and when I choose the 100% modus it shows the image in the fit modus. In the develope module I see some rare issues. When I copy the develope settings of a image to another image I see some rare contours in shades of different images in the image (sometimes more then one e.g. 2 contours from total different images). For me this is totally unacceptable. I didn't have copied local adjustments.
My emailadress is showed with an x and that is also not the right one. It is firstname.lastname@example.org in stead of harry.timmermansx.com. My operating system is OS Catalina 10.15.7.
Be sure to include the first ten lines from Help > System Info. Also click Like and Follow at the bottom of the first post. That will make it a little more likely that Adobe will prioritize a fix, and you'll be notified when the bug's status changes.
As a workaround, try setting Preferences > Performance > Use Graphics Processor to Off. That hasn't helped others in that bug-report thread, but your symptoms are sufficiently different that it's a worth a quick try.
I also agree with the recommendation to try rolling back to LR 10.0:
I have had la ost connection with my drive on which the images are and now I have enabled the connection again the problems are gone. I have also removed the previews what I think can also cause the problems.