query_end
Description:
public signal void query_end ()
Emitted when the session manager is about to end the session.
This signal is only emitted if [property@Gtk.Application:register-session] is `TRUE`. Applications can connect to this signal and call [ method@Gtk.Application.inhibit] with `GTK_APPLICATION_INHIBIT_LOGOUT` to delay the end of the session until state has been saved.