Dear Maintainer,
Java Applications (like Mediathekview, Gpsprune) are always shown fullscreen in
Gnome3, there are no buttons (close, resize, maximize) in the titlebar, hotkeys
to resize (Alt-F9, Alt-F10, ...) do not work, neither does doubleclicking or
moving the mouse to the top left corner in order to show the other applications
or favorites.
The only way to change to other applications is Alt-Tab or closing the Java-
Application (Alt-F4 works).
This only happens using the Gnome-shell, on other desktops like XFCE or
Cinnamon, Java applications behave normal like any other window, showing
buttons in the titlebar, reacting to hotkeys as expected.