This started a couple of weeks ago and persisted through multiple updates.
Upon login it would take longer than usual for the animation into Overview to run and for all the icons to appear both on the panel and the dock.
Then during usage, maximized window title bars would become hidden behind the panel, double click to maximize on the title bar would stop working. All the icons on the panel would disappear. Screen blank time would be reduced to 30 seconds down from 8 minutes, even the login screen would display weird behavior sometimes having the password input box and the username and image completely hidden.
I tried disabling extensions, using Xorg, Gnome Classic, nothing seems to help.
I have not found a way to reproduce the error at will. It seems to happen randomly. Sometimes, everything would suddenly go back to normal for a few minutes then break again.
Edit:
Rebasing to stable seems to fix it for now.