Why do you expect that Edge wouldn’t adopt Google-like MV3 along with Chrome?
Microsoft adopted Chromium in order to minimise development costs in a product it doesn’t see as core, something which would be incurred if it had to maintain its own fork of mv3, and is incentivized through Bing to pursue a similar approach.
This is not correct.
arewefastyet.com shows very clearly that although chrome beats firefox in some benchmarks, firefox trades blows with it and is similar to or faster in others.
I live in fear that the Phoronix forums will federate…