Earlier quoted context omitted.
What does any of that have to do with supporting the WebExtension open specification? It sounds like, to me, I can't ship a WebExtension for Safari because I don't own a Mac. Is that right? Does that sound right to you?
Yes it does sound right. Do you ship untested software?
Because there are more browsers than any person could conceivably have time to rigorously, thoroughly test. Yes, things like Browserstack exist.
But why do I have to test my Web Extension differently from my website. Should Safari start blocking websites whose TLS certificate lacks a "issued-to-a-mac" extension?