iCloud Passwords extension not working in Firefox on macOS Sequoia

I'm on macOS Sequoia (fully updated), and the iCloud Passwords extension for Firefox has stopped working. It was functioning fine before, but I’m not sure exactly when it broke — it seems to have stopped working randomly.

Details:

• macOS Sequoia, fully updated

• iCloud Keychain is enabled

• 2FA is active

• iCloud account is signed in and syncing normally

• Extension is installed from the official Mozilla add-on store

• Was working fine and seemingly randomly stopped working recently

• Tested in:

• Firefox (official release)

• Zen Browser (a Firefox-based browser)

Issue:

The extension is either inactive, doesn’t load, or fails to autofill anything. I’ve tried:

• Reinstalling the extension

• Restarting the browser and my Mac

• Signing out and back into iCloud

• Toggling iCloud Keychain

• Trying it on both Firefox and Zen

It shows me this:

Then when I click on it it takes me here:

but no code ever gets sent.

Here is info about my mac:

If the official solution is “just use Safari,” I’d rather carve my passwords into a stone tablet and carry it around.

Is this a known compatibility issue with Sequoia or recent Firefox updates?

Could Apple have silently broken support for non-Safari browsers again?

Any fixes or workarounds would be appreciated.