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
We need more browser options, not just Firefox and 20 versions of chrome.
I completely agree, but don’t forget that WebKit exists too on Mac and Linux with about the same market share as Firefox (at least based on w3school’s stats). Chrome/Blink dominate but all hope is not lost and there are more options, they’re just small. I think focusing on embracing Firefox/Gecko as it has so much momentum and community already is the most productive way forward though
The only reason WebKit has any market share left is because iOS/iPadOS forces it on their users even if you try to use other browser