plugins_url

	 *                     if no path is specified.
	 */
	return apply_filters( 'content_url', $url, $path );
}

/**
 * Retrieves a URL within the plugins or mu-plugins directory.
 *
 * Defaults to the plugins directory URL if no arguments are supplied.
 *
 * @since 2.6.0
 *
 * @param string $path   Optional. Extra path appended to the end of the URL, including
 *                       the relative directory if $plugin is supplied. Default empty.
 * @param string $plugin Optional. A full path to a file inside a plugin or mu-plugin.
 *                       The URL will be relative to its directory. Default empty.
 *                       Typically this is done by passing `__FILE__` as the argument.
 * @return string Plugins URL link with optional paths appended.
 */
function plugins_url( $path = '', $plugin = '' ) {

	$path          = wp_normalize_path( $path );
	$plugin        = wp_normalize_path( $plugin );
	$mu_plugin_dir = wp_normalize_path( WPMU_PLUGIN_DIR );

	if ( ! empty( $plugin ) && 0 === strpos( $plugin, $mu_plugin_dir ) ) {
		$url = WPMU_PLUGIN_URL;
	} else {
		$url = WP_PLUGIN_URL;
	}

	$url = set_url_scheme( $url );

	if ( ! empty( $plugin ) && is_string( $plugin ) ) {
		$folder = dirname( plugin_basename( $plugin ) );
		if ( '.' !== $folder ) {
			$url .= '/' . ltrim( $folder, '/' );
		}