diff --git a/wp-includes/Text/Diff.php b/wp-includes/Text/Diff.php
index 0f13b0fe5a..1d5b3859c5 100644
--- a/wp-includes/Text/Diff.php
+++ b/wp-includes/Text/Diff.php
@@ -350,15 +350,12 @@ class Text_MappedDiff extends Text_Diff {
  *
  * @access private
  */
-class Text_Diff_Op {
+abstract class Text_Diff_Op {
 
     var $orig;
     var $final;
 
-    function &reverse()
-    {
-        trigger_error('Abstract method', E_USER_ERROR);
-    }
+    abstract function &reverse();
 
     function norig()
     {
diff --git a/wp-includes/version.php b/wp-includes/version.php
index ba3dd2d24b..0c86cc481b 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.7-alpha-59105';
+$wp_version = '6.7-alpha-59106';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.