Ask HN: Any Decent Firefox Alternatives?

I've been using Firefox for a while now, but I have some issues with it:

1. I need to switch to chrome for various products such as Google Meet (works on Firefox, but I ran into performance (call quality) issues).

2. I often find sites with bad support for Firefox, and I need to again open a second browser (usually Chrome) to check them out.

3. It seems that in the past... long time, they have a talent of making Firefox worst. I still like it if it wasn't for the other 2 issues, but who can tell in 1 year.

Due to the above I was looking for a browser (one, I don't like having multiple on my machine but not sure if the Google Meet performance upgrade is just in Chrome or Chromium) which is as fast as Firefox, has a nice UI and preferably a bit more privacy oriented (not much, just a bit more).

Any ideas? (Currently checking out Vivaldi, but read a lot about performance issues + I don't really like the default UI yet).