Firefox on PC and Android. I've been using it almost since it came out.
But in the early days, the UI was super slow and extensions tended to slow it even more, so I moved to Chrome for a few years.
Then back to Firefox, but the devs caught an attitude and didn't want to listen to users, so I moved to Edge (Chromium) for a couple of years. Apparently, the Firefox devs did end up listening, so it's all good again.