There are definitely differences between mac and windows (possibly linux) when it comes to font availability/rendering(maybe?)
I've seen more than once a mac design use some font in a light weight that comes across almost invisible on Windows. I'm the only windows guy at our shop and "everyone has access to windows VMs to test" (lol)
Outside of that, now that Edge is on Chromium most of our edge cases seem to be Safari these days (everyone uses chrome/firefox except a couple management using Safari).
Which all in all I guess is a testament to our lack of full browser testing :)
¯\_(ツ)_/¯