Encountered this today on Edge macOS. Haven’t been able to reproduce it so maybe it was something one off.
So far, whenever I’d encounter a website that supports passkeys, Bitwarden grabs the request and shows me its prompt to fill the passkey. Today, along with Bitwarden I got a prompt from Edge asking for access to fill passkeys (I forget the exact message) and then a prompt from macOS asking whether it’s OK to grant access to Edge to passkeys. I clicked yes to both, and since then the Bitwarden prompt stopped coming up. Looks like Edge was grabbing the prompt first.
The fix was to go to Edge settings (use this URL edge://wallet/settings) and flip this to Off.
I don’t know if this was always Off or if it’s a new setting (unlikley). Worse, turning it back On doesn’t stop Bitwarden from working any more… so I have no idea if this does anything or why the issue started happening.
On macOS I do see Edge has access to passkeys coz of what I allowed earlier, so it did do something.
Chalk this one up to weirdness.