On the occasions I summon a hero or troop that I intend to keep, it would be great if I could favorite it right then and there, from the summons window.
Right now I can click the question mark at the top right, but then I don’t have the option to lock that hero / troop (the way I would if I hit the question mark from any other window. Instead, I have to go to my hero / troop inventory and remember to do it there.