diff --git a/wp-includes/media.php b/wp-includes/media.php
index 260db26cac..2b46167afc 100644
--- a/wp-includes/media.php
+++ b/wp-includes/media.php
@@ -1857,6 +1857,12 @@ function wp_filter_content_tags( $content, $context = null ) {
 			if ( $filtered_image !== $match[0] ) {
 				$content = str_replace( $match[0], $filtered_image, $content );
 			}
+
+			/*
+			 * Unset image lookup to not run the same logic again unnecessarily if the same image tag is used more than
+			 * once in the same blob of content.
+			 */
+			unset( $images[ $match[0] ] );
 		}
 
 		// Filter an iframe match.
@@ -1871,6 +1877,12 @@ function wp_filter_content_tags( $content, $context = null ) {
 			if ( $filtered_iframe !== $match[0] ) {
 				$content = str_replace( $match[0], $filtered_iframe, $content );
 			}
+
+			/*
+			 * Unset iframe lookup to not run the same logic again unnecessarily if the same iframe tag is used more
+			 * than once in the same blob of content.
+			 */
+			unset( $iframes[ $match[0] ] );
 		}
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 2caf2499c6..a1c93a42b5 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.0-alpha-53148';
+$wp_version = '6.0-alpha-53149';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.