I just installed the Windows Update KB5030310 and Passkeys now work perfectly fine in Firefox. The Windows Hello menu allows me to use Passkeys stored on my smartphone. Even Edge and Chrome now use the Windows Hello menu instead of their own Passkey ...
It seems that Windows Hello soon also supports passkeys that are stored on the phone. Thus, passkeys could then also be used in Firefox and native apps.https://blogs.windows.com/windows-insider/2023/06/22/announcing-windows-11-insider-preview-build-2...
I would also like to see this feature, but Apple needs to implement an add-on for Firefox like they did for Chrome: https://chrome.google.com/webstore/detail/icloud-passwords/pejdijmoenmkgeppbflobdenhhabjlaj