diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 8df5788119..68d865089f 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -6295,13 +6295,14 @@ function send_frame_options_header() {
  * @since 4.3.0 Added 'webcal' to the protocols array.
  * @since 4.7.0 Added 'urn' to the protocols array.
  * @since 5.3.0 Added 'sms' to the protocols array.
+ * @since 5.6.0 Added 'irc6' and 'ircs' to the protocols array.
  *
  * @see wp_kses()
  * @see esc_url()
  *
  * @return string[] Array of allowed protocols. Defaults to an array containing 'http', 'https',
- *                  'ftp', 'ftps', 'mailto', 'news', 'irc', 'gopher', 'nntp', 'feed', 'telnet',
- *                  'mms', 'rtsp', 'sms', 'svn', 'tel', 'fax', 'xmpp', 'webcal', and 'urn'.
+ *                  'ftp', 'ftps', 'mailto', 'news', 'irc', 'irc6', 'ircs', 'gopher', 'nntp', 'feed',
+ *                  'telnet', 'mms', 'rtsp', '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.
  */
@@ -6309,7 +6310,7 @@ 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', 'sms', 'svn', 'tel', 'fax', 'xmpp', 'webcal', 'urn' );
+		$protocols = array( 'http', 'https', 'ftp', 'ftps', 'mailto', 'news', 'irc', 'irc6', 'ircs', 'gopher', 'nntp', 'feed', 'telnet', 'mms', 'rtsp', 'sms', 'svn', 'tel', 'fax', 'xmpp', 'webcal', 'urn' );
 	}
 
 	if ( ! did_action( 'wp_loaded' ) ) {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 33b2b3547e..c89b4ad65e 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.6-alpha-49054';
+$wp_version = '5.6-alpha-49055';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.