Firefox 77 / 78 Beta vs. Chrome 83 Linux Browser Benchmarks
For the ARES-6 JavaScript benchmark, Chrome continues to run much faster than any of the recent Firefox releases on Linux...
One of the few JavaScript scenarios where Mozilla Firefox leads Chrome is with Mozilla's own Kraken benchmark albeit the lead is very minuscule.
Or in moving to Octane, Chrome 83 is around 27% faster than Firefox 77.
Firefox does lead Chrome slightly in the WebXPRT benchmark.