A full detailed list: https://caniuse.com/?compare=firefox+101,chrome+102&compareC...
If anything, it shows the damage of a browser-tech monopoly which Edge and Brave aren't helping with.
This is bad for Firefox because developers will eventually (and some still do) will simply stop supporting Firefox due it being so slow to catch up. Chrome already has such a huge market that a lot of web devs already don't care (e.g. Microsoft Teams).
What does this signify? It's the death of Firefox unless Firefox pulls a miracle here. Chrome is leading, all the devs are following, and they leading by leaps and bounds. Firefox is forced to catch up which causes frustration among users.
How long before Firefox gets tired of playing catch up and simply becomes irrelevant?
I am not happy about this. This is clearly bad but inevitable. The only other real competitor is WebKit which is restricted to Apple only. A huge market still. But Google's monopoly over the browsing market will only cause harm in the long run. Even though it will make devs jobs a lot easier.
Coincidentally, Brave believes they are privacy-invasive and don't support those features either (last paragraph in the article)[0].
Firefox, as with all other browsers aside from Safari, will remain with less than 5% market share for the foreseeable future. But I'd much rather continue supporting different browser engines than use a skinned Chromium to uphold the status quo.
[0] https://www.cnet.com/tech/computing/google-plan-for-chrome-c...
Mozilla, Apple, and Brave all disagree (as do I).
The overarching theme of your writing on this topic is that Chrome can just spit out Web 'features' at random and unless Firefox implements all of them immediately it is dying. I hope you can try to understand that not only is this not an accurate assessment, but maybe also that Firefox has value beyond being a copy of Chrome.
Mozilla needs to step up and find ways to expose such APIs though, because they are useful. Just saying "no" without proposing a solution is a sure way to lose. There's a bit of hope recently with the implementation of WebMIDI in Gecko.
It's telling that the only browser vendor that feels this way has the logo of one of the two most privacy invading companies in existence.