https://lists.gnome.org/archives/gtkmm-list/2012-June/msg00042.html
Re: error message from gtk::appchooserdialog
error messagegtk
https://gnome.pages.gitlab.gnome.org/gtkmm/classGtk_1_1AppChooserDialog.html
gtkmm: Gtk::AppChooserDialog Class Reference
gtkclassreference