Certain features that I depend on (particularly midi input) are only available in chrome as of right now, so I honestly only test it in chrome, though most of the basic functionality ought to work in other browsers.
This is the point where I stop and say "oh well, wait another year and maybe then..."
"Evergreen browsers only" is reasonable to ask for lots of sites; but "This site only works properly in the Chrome browser" gives me unpleasant flashbacks to when this notice was everywhere, but the browser was "IE5".