I am from Enpass Password Manager team and writing on behalf of Enpass.
First of all many thanks for supporting third party password managers in Opera Mini browser for iOS. We have tested the same feature with Enpass Password Manager, but it doesn't work. Although Opera Mini shows Enpass icon in the extension list, but it doesn't auto-fill the login details.
We have modified a few things in our development version to make it work with Opera, but still it is not autofilling details supplied by our extension.
So I will really appreciate if you can let us know where to contact for this issue (any developer support email etc.) to know what are additional changes that are required to make Enpass work with Opera Mini.
Enpass Password Manager