looks like rendering adblockers extensions obsolete with manifest-v3 was not enough so now they try to implement DRM into the browser giving the ability to any website to refuse traffic to you if you don't run a complaint browser ( cough...firefox )
here is an article in hacker news since i'm sure they can explain this to you better than i.
and also some github docs
The thing is mv3 is not needed nor wanted by anyone, they are actively shoving an unnecessary product down our throats to show us more ads.
I will keep on using Firefox and Librewolf until the web goes back to webpages that load in text only browsers in less than 2 secs