MyCSS_VALUES_COLOR_FUNCTION_ID_HWB

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C)
enum MyCSS_VALUES_COLOR_FUNCTION_ID_HWB = mycss_values_color_function_id.MyCSS_VALUES_COLOR_FUNCTION_ID_HWB;

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