You can open your app’s window on top of all other open application windows with the below code:
windowController?.showWindow(self)
NSApp.activate(ignoringOtherApps: true)
For example, in my app––Presentify––when you click on ‘Preferences’, the Settings window opens up on top of all other
applications. With just windowController?.showWindow(self)
, the window would open fine, but it won’t be visible to the
user if other apps are open.