c_gtk_icon_set_render_icon_surface

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
cairo_surface_t* function(GtkIconSet* iconSet, GtkStyleContext* context, GtkIconSize size, int scale, GdkWindow* forWindow) c_gtk_icon_set_render_icon_surface;

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