We’re going to have a serious problem on our hands soon with compatibility. I’m a software dev and I’m already seeing a few issues here and there where Chrome is being treated as the default expected browser and features don’t work on Firefox.

Firefox doesn’t support a fair few Chrome features because of security and privacy reasons, such as WebHID, WebUSB, etc.

Devs, please stop using those features. I know it’s tempting, but they’re basically bribes to encourage you to sell out to Google. Don’t do it.

Most “Chrome-only” web applications I have to use I can get around just by changing my user agent string and everything works fine. I try not to use that stuff when I can, though.
Some of the older stuff is indeed that way, but there are more and more features which Firefox can’t support. Web-based custom keyboard configuration tools, tools to flash phone firmware, and one niche MiniDisc tool all are chrome-only things I’ve had to open Chrome to use

tools to flash phone firmware

Yep. Forgot I had to use Chrome on Windows to flash GrapheneOS.

Wait is this real? That’s hilarious

grapheneos.org/install/web#prerequisites

Technically it works on Linux, but I didn’t feel like installing a Chromium browser to do it at the time.

GrapheneOS web installer

Web-based installer for GrapheneOS, a security and privacy focused mobile OS with Android app compatibility.

GrapheneOS
you don’t have to, there’s no need for that. they have a normal flashing tool too
we are really really better off without features that grant any website such deep access to our systems just by a single click, trust me. this is a security nightmare, especially looking at people who don’t understand computers and those who instant allow permissions by reflex.
This is my experience. They are just taking your default agent and throwing up a message because they can’t be assed to do minimal testing in FF.