This is not on any workboard. But I tested it with 4win-Beta-64 and the error shown in Kleopatra is now "Unusable public key".
So I'll put it on vsd33.

The changes broke saving of groups after editing. See T7181#190402 and T7181#190448. -> T7268: Kleopatra: Existing groups are not saved after editing them

In T7019#190282, @aheinecke wrote:

I would vote anyway for hiding the smartcard tab if it has no information, just so that we are not confusing, I can otherwise imagine support questions like: "It says something about smartcards, do I need such a smart card?" As smartcards for crypto is not something generally known by users, i assume.

Just thinking about this, we have at least one customer configuration that uses KXMLGui to hide all smartcard actions and the view. And one other that disables certify actions everywhere. We need to check that this still works with the new details view.