diff --git a/core/includes/common.inc b/core/includes/common.inc
index 197db87..96e6bd3 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -911,7 +911,7 @@ function valid_number_step($value, $step, $offset = 0.0) {
  *   check_plain() being called on it. However, it can be passed to functions
  *   expecting plain-text strings.
  *
- * @see check_url()
+ * @see \Drupal\Component\Utility\Url::stripDangerousProtocols()
  */
 function drupal_strip_dangerous_protocols($uri) {
   return Url::stripDangerousProtocols($uri);
@@ -932,7 +932,8 @@ function drupal_strip_dangerous_protocols($uri) {
  *   Drupal\Core\Template\Attribute, call drupal_strip_dangerous_protocols()
  *   instead.
  *
- * @see \Drupal\Component\Utility\String::stripDangerousProtocols()
+ * @see \Drupal\Component\Utility\Url::stripDangerousProtocols()
+ * @see \Drupal\Component\Utility\String::checkPlain()
  */
 function check_url($uri) {
   return String::checkPlain(Url::stripDangerousProtocols($uri));
@@ -983,7 +984,6 @@ function filter_xss_admin($string) {
  *   An XSS safe version of $string, or an empty string if $string is not
  *   valid UTF-8.
  *
- * @see drupal_validate_utf8()
  * @see \Drupal\Component\Utility\String::filterXss()
  *
  * @ingroup sanitization
@@ -995,16 +995,16 @@ function filter_xss($string, $allowed_tags = array('a', 'em', 'strong', 'cite',
 /**
  * Processes an HTML attribute value and strips dangerous protocols from URLs.
  *
- * @param $string
+ * @param string $string
  *   The string with the attribute value.
  *
- * @return
+ * @return string
  *   Cleaned up and HTML-escaped version of $string.
  *
- * @see \Drupal\Component\Utility\String::filterBadProtocol()
+ * @see \Drupal\Component\Utility\Url::filterBadProtocol()
  */
 function filter_xss_bad_protocol($string) {
-  return String::filterBadProtocol($string);
+  return Url::filterBadProtocol($string);
 }
 
 /**
diff --git a/core/lib/Drupal/Component/Utility/String.php b/core/lib/Drupal/Component/Utility/String.php
index 26e74f9..0feedf8 100644
--- a/core/lib/Drupal/Component/Utility/String.php
+++ b/core/lib/Drupal/Component/Utility/String.php
@@ -217,7 +217,7 @@ public static function filterXss($string, $allowed_tags = array('a', 'em', 'stro
   /**
    * Processes an HTML tag.
    *
-   * @param array $m
+   * @param array $matches
    *   An array with various meaning depending on the value of $store.
    *   If $store is TRUE then the array contains the allowed tags.
    *   If $store is FALSE then the array has one element, the HTML tag to process.
@@ -228,15 +228,15 @@ public static function filterXss($string, $allowed_tags = array('a', 'em', 'stro
    *   If the element isn't allowed, an empty string. Otherwise, the cleaned up
    *   version of the HTML element.
    */
-  protected static function xssSplit($m, $store = FALSE) {
+  protected static function xssSplit($matches, $store = FALSE) {
     static $allowed_html;
 
     if ($store) {
-      $allowed_html = array_flip($m);
+      $allowed_html = array_flip($matches);
       return;
     }
 
-    $string = $m[1];
+    $string = $matches[1];
 
     if (substr($string, 0, 1) != '<') {
       // We matched a lone ">" character.
diff --git a/core/lib/Drupal/Component/Utility/Url.php b/core/lib/Drupal/Component/Utility/Url.php
index 33dc597..f0f7dc0 100644
--- a/core/lib/Drupal/Component/Utility/Url.php
+++ b/core/lib/Drupal/Component/Utility/Url.php
@@ -8,7 +8,7 @@
 namespace Drupal\Component\Utility;
 
 /**
- * Helper to class to support filtering bad protocols from an url.
+ * Helper class to support filtering bad protocols from an url.
  */
 class Url {