I have TIVO Romeo and two minis, and Plex Pass. I have been reading about the problems with 126.96.36.19933 and have been trying to correct the problem, but I am limited in my understanding of Plex. As a Plex Pass member, I was updated and have been having problems ever since. I don't have the earlier version to revert to.
Look in \AppData\Local\Plex Media Server\Updates\ for the old version.
Call Tivo about the app update. They roll them out over time. Told me about two weeks to get them out to everyone.
I now have the most recent Tivo update 20.7.1.RC2-USA-6-846 and the problems continue (I also have Plex Pass). I will keep following the other posts. Also of our three computers I can't get the latest PMS to function. I have tried several times to uninstall and reinstall and it still calls for a download when I launch. I am going to take it easy and monitor for awhile with the hopes that new versions will soon come out.