Passkey on Safari results in error "PublicKeyCredential" after upgrade to Mac OS 15.4

Hello,

I’ve run into an issue with using passkeys stored in 1Password when signing in to Oracle Single Sign-On from Safari on macOS.

macOS version: Sequoia 15.6.1
Safari version: 18.6
1Password app version: 8.11.6
1Password Safari extension: enabled
Steps to reproduce:

Generate and store a passkey for Oracle SSO using Firefox on macOS (works fine).
Open the Oracle SSO login page in Safari.
1Password correctly offers the saved passkey.
After selecting the passkey, the login flow fails with the following error in the console:
TypeError: Can only call PublicKeyCredential.toJSON on instances of PublicKeyCredential

Expected behavior:
The saved passkey should authenticate successfully in Safari, just as it does in Firefox.

Actual behavior:
Safari shows the error above and login fails.

Notes:

The same passkey works correctly in Firefox (both creation and login).
In Safari, it looks like the Oracle page expects a native PublicKeyCredential object, but 1Password’s bridge is returning something different.
This makes Oracle SSO unusable with passkeys via Safari + 1Password.
Could you please confirm if this is a known compatibility issue with Safari and if there’s a workaround?

Thanks!