as described in the discussion title, I see that string under every entity with an OTP code generator. I'm using the last beta published on TestFlight, the one listed here: https://app-updates.agilebits.com/product_history/OPI4#v70303003
Editing it, there is no any trace of that string to change/delete.
Reproduced on iPhone X.
1Password Version: 5.7.3 (70303003)
Extension Version: Not Provided
OS Version: iOS 12.3.1 (16F203)
Sync Type: Not Provided