Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 44730)
+++ wp-includes/functions.php	(working copy)
@@ -1,4 +1,4 @@
-<?php
+<?php
 /**
  * Main WordPress API
  *
@@ -5695,6 +5695,7 @@
  * @since 3.3.0
  * @since 4.3.0 Added 'webcal' to the protocols array.
  * @since 4.7.0 Added 'urn' to the protocols array.
+ * @since 5.x.x Added 'skype' and 'sms' to the protocols array.
  *
  * @see wp_kses()
  * @see esc_url()
@@ -5703,15 +5704,15 @@
  *
  * @return string[] Array of allowed protocols. Defaults to an array containing 'http', 'https',
  *                  'ftp', 'ftps', 'mailto', 'news', 'irc', 'gopher', 'nntp', 'feed', 'telnet',
- *                  'mms', 'rtsp', 'svn', 'tel', 'fax', 'xmpp', 'webcal', and 'urn'. This covers
- *                  all common link protocols, except for 'javascript' which should not be
- *                  allowed for untrusted users.
+ *                  'mms', 'rtsp', 'skype', 'sms', 'svn', 'tel', 'fax', 'xmpp', 'webcal', and 'urn'.
+ *                  This covers all common link protocols, except for 'javascript' which should not
+ *                  be allowed for untrusted users.
  */
 function wp_allowed_protocols() {
 	static $protocols = array();
 
 	if ( empty( $protocols ) ) {
-		$protocols = array( 'http', 'https', 'ftp', 'ftps', 'mailto', 'news', 'irc', 'gopher', 'nntp', 'feed', 'telnet', 'mms', 'rtsp', 'svn', 'tel', 'fax', 'xmpp', 'webcal', 'urn' );
+		$protocols = array( 'http', 'https', 'ftp', 'ftps', 'mailto', 'news', 'irc', 'gopher', 'nntp', 'feed', 'telnet', 'mms', 'rtsp', 'skype', 'sms', 'svn', 'tel', 'fax', 'xmpp', 'webcal', 'urn' );
 	}
 
 	if ( ! did_action( 'wp_loaded' ) ) {