When viewing Ente Auth in the Installed list, I get the message:
This version is signed with a different signature than the one installed on your device.
I’ve never seen this before. How should I fix this? I am using Droid-ify.
Perhaps you installed play store version(?)
Good point. Had a look and the Play Store (at some point) took over. I normally do F-Droid first, but guess I’m stuck with this now. 
If Ente Auth provides a Backup/Restore feature just do backup then uninstall the play store version install f-droid version and restore all data you backed up.
Yeah, I suppose I could do that. I’ll create a sync chain with another device (e.g.computer) as well, in case the export of the codes fail. It’s just how Play Store weasels it way to own apps that come from other stores, that grinds my gears and then we have to go through the whole song and dance to fix it - but that depends on whether the app has a way to do import/export.
Something interesting to note is that this should be impossible. Google Play doesn’t force install/update/replace apps with different signatures as that would violate a pretty big portion of the Android security model. The only way this would be technically feasible is if the device had that security restriction lifted which would be a cause for concern if that is the case. (For the record if you are on a stock Google Android Device given how Privileged Google Play is i don’t doubt that they could bypass that if they wanted to. I am just noting that they didn’t design it to do that.)
But more than likely if i had to give a honest guess you may have accidentally installed it from the Play Store without remembering or realizing and then it caught up to you now. It happens to me sometimes too with Droid-ify and the Aurora Store with the same hosted apps but different signatures. and it’s pretty annoying. Either way likely nothing to worry about. After you uninstall then reinstall (if you haven’t already) this shouldn’t happen again. If it does you may want to be a bit cautious as that really is not supposed to happen and could indicate something more problematic is going on.