Looks like Twitter messed up their CSP rules for inline vids about two weeks ago, and nobody cares:
@raucao It looks like it only affects Firefox. There's the same problem on many other websites.
@kdy I didn't see it on any websites yet, and it's clearly a CSP block.
@raucao Well, people are saying it was fixed on the latest Firefox version, so maybe check that. But yeah, as a Blink user, everything's working.
@kdy I know it's working in Chrome, otherwise Twitter would've fixed it immediately. :/
@raucao works fine here on chrome
@athosbr99 Yes, it's only in FF.
@raucao i have nighly installed here, lemme check out
@raucao got some erros from god knows where but the video is playing
also wtf they have done in this nightly build https://mastodon.social/media/XzsraLQdDw3GzL4sO38