it’s better to avoid using it and report web compatibility problems
It would be if sites were truly incompatible, but developers know Chrome/Chromium dominates the market and instead of bothering checking compatibility with firefox, they just preemptively block Firefox since that’s an easier “fix”.
That’s assuming the vendor isn’t Google and doesn’t have a vested interest in Chrome hegemony.
Still. Finding a site that doesn’t work and reporting it absolutely is the way to go.