AquaSalMenu::setDefaultMenu() is generally called when the key window has been closed. When not in native full screen mode, macOS appears to automatically set the key window. However, closing a native full screen window sometimes causes the application to drop out of full screen mode even if there are still native full screen windows open. So, if the application is active, activate all windows to force macOS to set the key to a window rather than leaving the application in a state where the key window is nil. Also, add a EnableNativeFullScreenWindows expert preference so that users can disable native full screen mode and make the green button in the titlebar zoom instead of switching to a full screen window. Change-Id: I3d9c538d784d7abcd5e75975ea00582768851ec7 Reviewed-on: https://gerrit.libreoffice.org/c/core/+/183229 Tested-by: Jenkins Reviewed-by: Patrick Luby <guibomacdev@gmail.com>