Node that had focus before popupFrame took over. When the popup is closed using a keyboard shortcut, this node will take focus again.
Assigned automatically if spawnPopup or spawnChildPopup is used, but otherwise not.
Used if FocusIO is not available; for old backend only.
previousFocusable, which is used with the new I/O system.
See Implementation
Node that had focus before popupFrame took over. When the popup is closed using a keyboard shortcut, this node will take focus again.
Assigned automatically if spawnPopup or spawnChildPopup is used, but otherwise not.
Used if FocusIO is not available; for old backend only.