I'm guessing that Omar meant "repeat" or "reapply" instead of "redo". Florian, I would like this feature also.
Please consider a function key shortcut that would repeat the last-run quick action, action, or action group on the current selection during the current Mp3tag session. If no actions had been executed during the current Mp3tag session, pressing the shortcut key would do nothing.
I have such a shortcut in my HTML editor and it uses F6 this way. That key does not seem to be assigned within Mp3tag so presumably it could be used here. And yes, I know about Alt+6. That is not the same because it merely displays the Actions list and then requires an additional click or key press to execute. And Alt+6 doesn't work for quick actions at all.
Sometimes I create a quick action for an operation that I know will never be needed again outside of the current folder. I apply that to the selection, but later decide that more files in the current folder need the same action. As it is now, I have to recreate the quick action from scratch all over again, which is tedious. For me, a function key "repeat current action" shortcut would be a real time-saver.