MyCSS_PROPERTY_COLUMN_RULE_WIDTH_MEDIUM

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_PROPERTY_COLUMN_RULE_WIDTH_MEDIUM = mycss_property_column_rule_width.MyCSS_PROPERTY_COLUMN_RULE_WIDTH_MEDIUM;

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