[FEATURE] Buttons should accept e.g. a StyledSpan for formatting the lables

[eras]

When adding keyboard shortcuts to the actions buttons have, it seems difficult to express the user that the binding exists.

One easy way would be to have a styled button (with e.g. one highlighted character, easily expressed with markdown), but unfortunately that's not supported at the moment. Buttons themselves could also have a way to add bindings to them, and then a way to show those bindings in the UI, but it would be a more complex solution.

There doesn't seem to be an alternative, other than making a custom implementation of a button.