Abstract: Provide a compatibility button in Firefox to enable pre-defined compatibility profiles for the most widely used web applications. Additionally, allow to create per-site profiles along with that functionality.
Some webservices discriminate users by their user agent string:
"A fix would be for Firefox to spoof its own user-agent string, so it represents itself as whatever the latest version of Edge is.", c.f. https://bugzilla.mozilla.org/show_bug.cgi?id=1623340#c5
Other services require hardware acceleration without any technical reason. In both cases, these services are online collaboration tools, but many more services are imaginable that behave this way.
Each day we can see people fighting against discrimination by culture, religion etc. But here we see how users are not presented the full functionality, just because they like to run specific software, even if that software is technically capable to provide the full experience. This is a form of discrimination as well.
I suggest to give these services their "Edge" string if this is what they want, and to give them their hardware acceleration, while still using Firefox and software decode, instead of being forced to other browsers. You can pre-deliver profiles for the most important web services. It is up to the users which browser they prefer, or if their software decode performance is satisfying for them.
This functionality makes even more sense in the context of having customizable profiles for a website. E.g. For 99% of websites you might not want to have third party cookies enabled, but for one website you might believe you need them. Or you might not like to have WebRTC enabled in general, but for some websites. Firefox is lacking the feature to enable this privacy relevant setting automatically by the URL to make this particular, trusted website work easily for a user. For this reason, we need a compatibility mode/button.
Keep fostering inclusion and make people collaborate together in a safe World Wide Web!