This action method searches for a candidate previous key view and, if it finds one, invokes
make to establish it as the first responder.
- macOS 10.0+
The message’s sender.
The candidate is one of the following (searched for in this order):
The current first responder’s previous valid key view, as returned by the
Valid Key View
Otherwise, the initial first responder’s previous valid key view, which may end up being