Comment by extheat

Cool! I recently wrote my own user script to do the same thing. It's going to be very hard to patch or detect this, as updating video element props don't trigger DOM updates. They would have to either do lots of JS prototype trickery or check for playback rate when doing adblock detection. One thing to keep in mind here though since you're doing DOM lookups every time anything on the page changes, is that there could be some small overhead in page render time, and also that using fixed CSS classes means any small change to page code could break the checks. In case it's a problem in the future, checking .innerText is a hacky way to workaround it.