tangentially related: what's everyone's solution for blocking autoplaying sticky videos? By that I mean the kind that usually shows up on news sites or tech blogs. It usually manifests as a "recommended" video that's totally unrelated to the article at hand, and stars playing without you clicking the play button. If you scroll past the video, many of them convert to a sticky mini player that stays around wherever you scroll.
I've tried changing the autoplay setting from "block audio" to "block audio and video", but that breaks sites, especially the ones that assume you have autoplay enabled and don't have controls available. It's also hard to know when something's broken. I see a static image and I'm left to wonder whether it's a video that's hasn't started yet or it's actually a picture. For some sites, blocking autoplay don't even prevent the videos from loading because they start video playback during an onScroll event, which makes the browser think the playback was user-initiated.