It works well but lately it has been unmuting some ads.

Mutes twitch ads. Unmutes when the ads are finished. The extension is working well.

Works half the time, very inconsistent.

Response to the dev -
It's completely random. sometimes it works and other times it doesn't, will post an update if i find out anything. Perhaps it could have an issue with another twitch extension i have, BetterTTV, FrankerFacez, Unwanted Twitch.

Update 31/5/24 -
Still randomly decides to play audio in an ad, i disabled the extensions mentioned above and issue remains, have no idea what is causing it, it's completely random. I would say it mutes 90% of the time but then randomly an ad will start playing with sound, very annoying. To fix it i usually have to fiddle about with restarting the page and disabling/enabling the extension.

You mentioned multiple tabs, not sure if that is still the issue or if you have actually fixed it, i always have multiple tabs open in Firefox, at least two at any given time, so perhaps it's still causing an issue.

Works as expected.

It just works, hate twitch ads, thank you thank you, was tired of doing it manually.