GNOME: make better use of the application menu
Issue generated from Tuleap's migration script. Originally submitted by: Stepan Salenikovich (ssalenik)
Modern GNOME DEs implement the application menu and so options such as 'About' and 'Help' should be displayed there. Ideally, when the application menu is used, the menu shouldn't be displayed in the application window. The gtk API provides a way to do this:
https://developer.gnome.org/gtk3/stable/GtkApplicationWindow.html
One possibility is to put everything that is currently in the header bar into the application menu, ie: Settings, About, Quit, and not display the "Ring" and "gears" menus in the header bar. And then put all these in the "gears" menu for envs that don't support the application menu.
See also:
https://developer.gnome.org/hig/stable/application-menus.html.en