I use LibreTorrent. It is available in F-Droid repos. Copy and paste magnet links and it downloads the files. You may want to use a vpn, depending on the country you are in.

The only downside is no BEP 52 support.

There are a moderate amount of tightly connected releasers who encode and release AV1. Just add av1 to any search on 1337x and you can find them.

Why not Firefox with uBlock Origin?

No

Doesn’t not being able to modify it would also imply that the information can not be parsed? Thus this consept falls apart immediately as the information would need to be able to be parsed so that it can be rendered?