GitHub - Alex313031/Mercury: Firefox fork with compiler optimizations and patches from Librewolf, Waterfox, and GNU IceCat.
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Firefox fork with compiler optimizations and patches from Librewolf, Waterfox, and GNU IceCat. - GitHub - Alex313031/Mercury: Firefox fork with compiler optimizations and patches from Librewolf, Wa...

I was looking for a non-chromium alternative browser to Firefox and found mercury. According to this site it is one of the fastest Firefox forks and also has optimizations from other well known forks like librewolf.