Web pages with infinite scroll get incredibly laggy

So I know these websites are kind of crap anyway, but I have issues with scrolling bsky.social (and other clients for it like witchsky) and twitter. The further into the timeline I get, the more frequently these webpages lag. They begin freezing every few seconds for a few seconds, during which they queue left or right clicks, page up/page down, and various other commands, only processing them once it unfreezes. Firefox itself still works during this freeze, e.g. opening the main menu. Also, I can still scroll up or down to a limited degree, though this just exposes empty, unrendered webpage until it unfreezes. bsky.social has had this problem for a long time, but twitter only recently developed this issue after I had to do a cache clear, cookie clear, etc. trying to log in a few weeks ago. Prior to that it didn't have this issue. Task manager hasn't really helped elucidate what's wrong, so it might be an about:config that I set or even an unruly extension, but I really don't know what to try.