WP_Theme_JSON::convert_custom_properties( string $value ): string

4208	private static function convert_custom_properties( $value ) {4209		$prefix     = 'var:';4210		$prefix_len = strlen( $prefix );4211		$token_in   = '|';4212		$token_out  = '--';4213		if ( str_starts_with( $value, $prefix ) ) {4214			$unwrapped_name = str_replace(4215				$token_in,4216				$token_out,4217				substr( $value, $prefix_len )4218			);4219			$value          = "var(--wp--$unwrapped_name)";4220		}4221 4222		return $value;4223	}