This is a nice site but people need to know that half of listed resources will only work in Chrome and its derivatives. Firefox does support U2F for example but Google, Facebook and others does not support U2F via FF on their resources. This situation is at least 1-2 year old and I suspect will keep like that for a long time.
What about other Chromium-based browsers such as Brave, Vivaldi, Opera?
Google does support U2F on Firefox. Just not for registering the key.
That's a great summary. Sadly, from what I see, hard key support is marginal.