On Wed, 2015-10-14 at 16:28 +0200, Stefan Salewski wrote: > I just got > > (test:2726): Gtk-CRITICAL **: gtk_main_quit: assertion 'main_loops != > NULL' failed Seems that they have adapted drawing.c for latest gtk 3.18.1 to new app style where no gtk_init() is called, but they still use gtk_main_quit () in close_window. I think that is wrong.