I have the same issue with my new Mac mini and new Magic Keyboard. The Touch ID option in 1Password Settings is greyed out. Touch ID works fine for unlocking the screen, etc. macOS 15.15.1 iPassword 8.10.54.
This feature works fine on my MacBook Air and Magic Keyboard when the laptop is closed (external monitor).
I have restarted both macOS and 1Password (of course)
I just migrated from an Intel Mac Book Pro to one of the new Mac minis (M4 chip). The Touch ID feature works fine for logging in / unlocking screen but the Touch ID option is greyed out in 1Password Settings->Security.
The 1Password Touch ID feature works fine on my Mac Book Air (M1) with the same model Magic Keyboard (external monitor). I have tried the usual fixes (restarting, turning on and off the Touch ID settings in System Settings->Touch ID & Password). After the migration I needed to download a new copy of 1Password (8.10.54). MacOS is 15.1.1 I'm wondering if 1Password does not recognize the combination of a non-laptop M-series computer with Magic Keyboard as being Touch ID capable. (This feature is the reason I bought the Magic (expensive) keyboard.)
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