Can anyone explain this for are you seeing it as well?
Running the latest of everything on a supervised install.
Please try reloading cache by Ctrl+F5.
I’m seeing this as well, both for Core and Supervisor.
Reloading cache did not help. It is occurring in the Android App and multiple browsers.
It usually clears up after a while; then it comes back. I can’t see any pattern related to anything I’m doing (reloads, restarts, …). This has been happening now for about 4 days.
Mine is doing the same thing, and one time I accidentally hit “Update” and it actually downgraded to 2021.3.3 
Thar is what I am seeing… comes and goes and it does downgrade.
I am running a supervised install.