Logging in to icloud.com is not possible when there is a choice of a passkey or password.
If the 1Password extension is not on, and I try to log in to icloud.com, I fill the panel of Apple, fill in my name, return, and I get a panel with a choice between login or passkey (two buttons "continue with Password" and "Sign in with Passkey"). I usually use the passkey.
When the 1Password extension is on, I try the same, the panel of apple does not change after return. I am stuck and cannot login.
I tested this with Chrome with the 1Password extension being the only extension "on" or "off" (I usually do not use Chrome). Likewise, I have tried this also with a Chromium based browser (Arc) and the effect was exactly the same. Finally, I have also tested this on Firefox, and the bug is identical.
If I test this with Safari, things works, which seems to indicate that the bug is the extension (I presume the safari extension is a very different code).
To be sure, I also tried to login to another site where passkey is enabled via 1Password (adobe) and the login mechanism workd perfectly
1Password Version: 8.10.36
Extension Version: 2.26.1
OS Version: macOS 14.5
Browser: Chrome, Firefox, Arc