I'm running LR 8.1 on a Mac (Sequoia 15.1.1), and there seem to be some really severe bugs. First off, some of the slider controls will suddenly disappear - I can see the number value, but not the slider itself (e.g. Temp under Color, but I can manually enter a new number for the temp, which is very time intensive when I'm trying to hit the sweet spot). In the Info section (metadata), the fields and their titles will initially appear, but if I've entered something, those fields may disappear and I only see the titles (and sometimes I can click on the solid grey area below the titles to make the text appear when highlighted, but not always). Closing and restarting LR seems to help for a bit.
Finally, the memory issue with LR has gotten even worse with this version. I have to close and restart the app a couple of times a day, and *never* leave it open overnight, because otherwise it'll freeze up, with a system message saying that it's using nearly *60GB* of application resources (!). Force quitting and restarting LR returns it to the normal range.
I used to be in charge of app development for a few companies, and I know how difficult it is to QA in all sorts of environments, virtual or real, but this is one of the largest batches of bugs I've yet seen out of one of Adobe's products. They still haven't fixed the disappearing metadata in the iPad version ...