They must have meant LibreWolf.

I've used it as a 2nd browser for past 2 years although on Speedometer benchmark it constantly gets a much lower score than Firefox. You can feel LibreWolf slower it on heavy sites like YouTube.

https://browserbench.org/Speedometer3.1/

I also notice Chromium browsers get lower score than official Chrome binary. Apparently Google make further modifications to Chromium before compiling (that they don't make public).