So basically it is already really hard to support all web browsers out there, since there is no "standard". So what you do is you limit yourself to a few, and display "Best played in browser X", because browser Y has these strange issues, and might introduce others with a new update, and the same for browser Z and F.
So if you make rich web content such as games, the ecosystem will automatically push itself to a limited amount of web browsers.
Let me explain: there is no true open standard (as explained at https://www.joelonsoftware.com/2008/03/17/martian-headsets/). You don't realize this until you make HTML5 games or apps, like when Google decided to break tons of HTML5 games with https://developers.google.com/web/updates/2017/09/autoplay-p...
So basically it is already really hard to support all web browsers out there, since there is no "standard". So what you do is you limit yourself to a few, and display "Best played in browser X", because browser Y has these strange issues, and might introduce others with a new update, and the same for browser Z and F.
So if you make rich web content such as games, the ecosystem will automatically push itself to a limited amount of web browsers.