There's tons... Firefox: https://addons.mozilla.org/en-US/firefox/addon/clearurls/ Android: https://github.com/svenjacobs/leon

Just in case, I’m using my own violentmonkey scripts rather than hoping for extensions, and everyone can do that too (now only on firefox, I guess, and maybe brave).

For example, I remove &t=<n> from urls that youtube added recently in addition to regular watch position restoration. This broke it for me and they don’t seem to plan a revert.

That is also used if you want to share a video at a particular timestamp with someone. E.g. check this out it happens 40s in. YouTube.com....&t=40s

A little downside, yeah, but these scripts can be easily toggled. What can't be easily done is finding my last timestamp in a 5h long vod when &t-in-history screws it up.