I have read the last post on this, August 2021, but none of the suggestions work. I can’t find “content” in settings, and there is no padlock icon on the address bar. Autoplay is so annoying that I can’t understand why there isn’t an obvious way to disable it permanently.
Expected result:
Find a way to permanently turn off autoplay on all websites.
which is very similar to your query. Amongst the replies, you’ll find mention of an extension that effectively blocks ALL autoplay - plus a discussion of risks associated with extensions.