fix alt-key stealing focus from current dock widget in gui * file-editor-interface.h: define purely virtual method menubar returning the editors menu bar * file-editor.h (menubar): implementaiton of method menubar * main-window.cc (main_window): intialize new class variabel for the editors menu bar depending on the editor in use (gui or external); (focus_changed): if new widget is one of the menubars, reset focus to currently active widget m_active_dock and just return; (prepare_to_exit): set m_active_dock to nullptr preventing setting focus to a widget that might not exist anymore during shutdown * main-window.h: new clas variable m_editor_menubar

--- a/libgui/src/m-editor/file-editor.h	Fri Nov 20 20:02:29 2020 +0100
+++ b/libgui/src/m-editor/file-editor.h	Fri Nov 20 23:25:42 2020 +0100
@@ -98,6 +98,8 @@
 
     QToolBar * toolbar (void) { return m_tool_bar; }
 
+    QMenuBar * menubar (void) { return m_menu_bar; }
+
     void insert_global_actions (QList<QAction*>);
 
     enum shared_actions_idx