diff --git a/includes/class-comment-walker.php b/includes/class-comment-walker.php
index 1c23dae..b16d541 100644
--- a/includes/class-comment-walker.php
+++ b/includes/class-comment-walker.php
@@ -4,6 +4,7 @@
 
 use WP_Comment;
 use Walker_Comment;
+use WP_Comment_Query;
 
 class Comment_Walker extends Walker_Comment {
 	/**
@@ -283,6 +284,10 @@ protected function html5_comment( $comment, $depth, $args ) {
 	 * @param  WP_Comment_Query $query Comment count.
 	 */
 	public static function comment_query( $query ) {
+		if ( ! $query instanceof WP_Comment_Query ) {
+			return;
+		}
+
 		if ( is_admin() ) {
 			return;
 		}
@@ -292,9 +297,9 @@ public static function comment_query( $query ) {
 		}
 
 		if ( ! empty( $query->query_vars['meta_query'] ) ) {
-			$query = current( $query->query_vars['meta_query'] );
+			$query_vars = current( $query->query_vars['meta_query'] );
 
-			if ( ! empty( $query['key'] ) && 'protocol' === $query['key'] ) {
+			if ( ! empty( $query_vars['key'] ) && 'protocol' === $query_vars['key'] ) {
 				return;
 			}
 		}
diff --git a/languages/webmention.pot b/languages/webmention.pot
index 5fc3963..4bd602e 100644
--- a/languages/webmention.pot
+++ b/languages/webmention.pot
@@ -2,10 +2,10 @@
 # This file is distributed under the MIT.
 msgid ""
 msgstr ""
-"Project-Id-Version: Webmention 5.3.0\n"
+"Project-Id-Version: Webmention 5.3.1\n"
 "Report-Msgid-Bugs-To: "
 "https://wordpress.org/support/plugin/wordpress-webmention\n"
-"POT-Creation-Date: 2024-05-13 07:52:14+00:00\n"
+"POT-Creation-Date: 2024-05-13 15:00:42+00:00\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=utf-8\n"
 "Content-Transfer-Encoding: 8bit\n"
@@ -313,28 +313,28 @@ msgstr ""
 msgid "DB Migration finished"
 msgstr ""
 
-#: includes/class-comment-walker.php:207
+#: includes/class-comment-walker.php:195
 msgid "Your comment is awaiting moderation."
 msgstr ""
 
-#: includes/class-comment-walker.php:209
+#: includes/class-comment-walker.php:197
 msgid ""
 "Your comment is awaiting moderation. This is a preview; your comment will "
 "be visible after it has been approved."
 msgstr ""
 
-#: includes/class-comment-walker.php:230
+#: includes/class-comment-walker.php:218
 #. translators: %s: Comment author link.
 msgid "%s <span class=\"says\">says:</span>"
 msgstr ""
 
-#: includes/class-comment-walker.php:250 templates/webmention-comment.php:67
+#: includes/class-comment-walker.php:238 templates/webmention-comment.php:67
 #. translators: 1: Comment date, 2: Comment time.
 #. translators: 1: date, 2: time
 msgid "%1$s at %2$s"
 msgstr ""
 
-#: includes/class-comment-walker.php:256
+#: includes/class-comment-walker.php:244
 msgid "Edit"
 msgstr ""
 
diff --git a/readme.md b/readme.md
index b189425..a3a2293 100644
--- a/readme.md
+++ b/readme.md
@@ -4,7 +4,7 @@
 **Tags:** webmention, pingback, trackback, linkback, indieweb  
 **Requires at least:** 4.9  
 **Tested up to:** 6.5  
-**Stable tag:** 5.3.0  
+**Stable tag:** 5.3.1  
 **Requires PHP:** 5.6  
 **License:** MIT  
 **License URI:** https://opensource.org/licenses/MIT  
@@ -100,6 +100,10 @@ While not all display options can be settings, we are looking to provide some si
 
 Project and support maintained on github at [pfefferle/wordpress-webmention](https://github.com/pfefferle/wordpress-webmention).
 
+### 5.3.1###
+
+* Fix fatal error
+
 ### 5.3.0 ###
 
 * Fix facepiles for FSE themes
diff --git a/readme.txt b/readme.txt
index 32614b7..34a9cfb 100755
--- a/readme.txt
+++ b/readme.txt
@@ -4,7 +4,7 @@ Donate link: https://notiz.blog/donate/
 Tags: webmention, pingback, trackback, linkback, indieweb
 Requires at least: 4.9
 Tested up to: 6.5
-Stable tag: 5.3.0
+Stable tag: 5.3.1
 Requires PHP: 5.6
 License: MIT
 License URI: https://opensource.org/licenses/MIT
@@ -100,6 +100,10 @@ While not all display options can be settings, we are looking to provide some si
 
 Project and support maintained on github at [pfefferle/wordpress-webmention](https://github.com/pfefferle/wordpress-webmention).
 
+= 5.3.1=
+
+* Fix fatal error
+
 = 5.3.0 =
 
 * Fix facepiles for FSE themes
diff --git a/webmention.php b/webmention.php
index 43e8d91..5608d2a 100755
--- a/webmention.php
+++ b/webmention.php
@@ -5,7 +5,7 @@
  * Description: Webmention support for WordPress posts
  * Author: Matthias Pfefferle
  * Author URI: https://notiz.blog/
- * Version: 5.3.0
+ * Version: 5.3.1
  * License: MIT
  * License URI: https://opensource.org/licenses/MIT
  * Text Domain: webmention