c_gtk_icon_theme_lookup_by_gicon_for_scale

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)
GtkIconInfo* function(GtkIconTheme* iconTheme, GIcon* icon, int size, int scale, GtkIconLookupFlags flags) c_gtk_icon_theme_lookup_by_gicon_for_scale;

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