diff --git a/wp-includes/js/thickbox/thickbox.js b/wp-includes/js/thickbox/thickbox.js
index 62ffb4b941..5470467a1e 100644
--- a/wp-includes/js/thickbox/thickbox.js
+++ b/wp-includes/js/thickbox/thickbox.js
@@ -76,10 +76,16 @@ function tb_show(caption, url, imageGroup) {//function called when the user clic
 	   		baseURL = url;
 	   }
 
-	   var urlString = /\.jpg$|\.jpeg$|\.png$|\.gif$|\.bmp$/;
+	   var urlString = /\.jpg$|\.jpeg$|\.png$|\.gif$|\.bmp$|\.webp$/;
 	   var urlType = baseURL.toLowerCase().match(urlString);
 
-		if(urlType == '.jpg' || urlType == '.jpeg' || urlType == '.png' || urlType == '.gif' || urlType == '.bmp'){//code to show images
+		if(urlType == '.jpg' ||
+			urlType == '.jpeg' ||
+			urlType == '.png' ||
+			urlType == '.gif' ||
+			urlType == '.bmp' ||
+			urlType == '.webp'
+		){//code to show images
 
 			TB_PrevCaption = "";
 			TB_PrevURL = "";
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 843a2ee09e..47e8f8a224 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-alpha-53450';
+$wp_version = '6.1-alpha-53451';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.