What if it's Google themselves? From my original post:
> [...] and that often includes Google sites/apps
What google site or service requires Chrome?
Sure, it's a lab experiment or whatever, but these are just words, and the effect is that I have to use a different browser to be able to use them, for absolutely no technical reason. (The LLM is running on Google's servers and provides plaintext. I think Firefox could handle that.)
Just visit this on Firefox if you want to see for yourself, including a big "install Chrome" call to action: https://labs.google.com/search/install
On Google Docs, paste as markdown, copy and paste from menus, paste without formatting, etc. only works on chrome. This functionality could be done with standard APIs, but instead google uses a hidden, pre-installed extension to implement it.
Offline mode doesn't work on firefox for either gmail or google docs.
Google doodles don't show up on Firefox Mobile, unless you spoof a chrome user agent.
Youtube has repeatedly had serious performance problems on Firefox.