title: Swift: How to prevent window to show up on launch?
body: <p>I am writing a macOS Cocoa application with Swift and I don't know how to prevent, that the main window shows up on application startup. I want to check first, if there is a new version available on the server: if there is one, a spash screen should appear. I don't know how to accomplish this and couldn't find good information too. I also don't know how to get rid of the windows standard buttons like for closing the window. Any help?</p>