GtkToolbar::insert_widget
void insert_widget(GtkWidget widget, string tooltip_text, string tooltip_private_text, int position);
Inserts a widget at the given position. The position minimum value is 0, and the maximum is the number of items on this toolbar.
The tooltip_text is the one being visible when the mouse hovers over the element. The tooltip_private_text is for context-sensitive help about this widget.
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