"Unable to unlock with biometrics" message when unlocking Safari extension on 2018 iPad Pro

Whenever the 1Password extension for Safari is locked and I click on the toolbar icon to unlock it, it seems like I should be able to unlock it with Face ID because there's the little Face ID icon the same as opening the main app, but whenever I click it, I get an error saying "Unable to unlock with biometrics" and I have no choice but to unlock with the master password.

I've tried disabling and re-enabling Face ID for the main app, to no avail. How do I get it to unlock the extension with Face ID? Because entering my password constantly is a massive step backwards. :(

1Password Version: 7.9.3
Extension Version: Not Provided
OS Version: iPadOS 15.2