Thanks for trying it out and describing your issue. I assume that you mean that you have the IdentityFile option configured for every connection in your config file?

That should work though, it might not list the file as an explicit detected key-based authentication method when you edit the connection (Might be listed as None), but it should still apply the identity file option you have set in the config.

If that is not happening, then this is a bug and I can investigate that.