Also from the official announcement (https://blog.mozilla.org/addons/2023/11/28/open-extensions-on-firefox-for-android-debut-december-14-but-you-can-get-a-sneak-peek-today/ ):
Starting December 14, 2023, extensions marked as Android compatible on addons.mozilla.org (AMO) will be openly available to Firefox for Android users.
“We’ve been so impressed with developer enthusiasm and preparation,” said Giorgio Natili, Firefox Director of Engineering. “Just a few weeks ago it looked like we might have a couple hundred Android extensions for launch, but now we can safely say AMO will have 400+ new Firefox for Android extensions available on December 14. We couldn’t be more thankful to our developer community for embracing this exciting moment.”
I don’t want to just block them though, I want to deny cookie use automatically and hide the popup
You haven’t consented to cookies until you click agree, so there shouldn’t be any difference if the website is GDPR compliant.
That’s a pretty big if. I’ve seen sites with banners at the top that say something along the lines of, “by dismissing this banner or continuing to use the site you’re consenting to cookies”