It clearly is, with hundreds of thousands of daily users. Maybe it's broken on some specific sites[1]; can you recall which sites those were?

Because it works, right now, on all the mainstream and popular sites, including every banking site I use it on, every shopping site, every wordpress site, every forum, subreddit, LLM/webchat, search engine, LoB and social networking site I used it on over the last decade and a half.

Actions speak louder than words - use FF, and then when you get to a site it doesn't work on, start Chromium, instead of complaining about the hours trying to fix it.

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[1] Note I am not saying that it is broken for you, I am saying that it is broken for specific sites.