diff --git a/src/wp-includes/html-api/class-wp-html-active-formatting-elements.php b/src/wp-includes/html-api/class-wp-html-active-formatting-elements.php
index a2c5d4f72452d..fb05a6e937499 100644
--- a/src/wp-includes/html-api/class-wp-html-active-formatting-elements.php
+++ b/src/wp-includes/html-api/class-wp-html-active-formatting-elements.php
@@ -144,11 +144,7 @@ public function push( AFE_Element|AFE_Marker $afe ): void {
 		 */
 		$count = 0;
 		foreach ( $this->walk_up_until_marker() as $item ) {
-			if (
-				$item->namespace === $afe->namespace &&
-				$item->tag_name === $afe->tag_name &&
-				$item->attributes === $afe->attributes
-			) {
+			if ( $item->is_equivalent( $afe ) ) {
 				if ( ++$count >= 3 ) {
 					return;
 				}
@@ -294,6 +290,23 @@ class AFE_Element {
 	/** @var WP_HTML_Token */
 	public $token;
 
+	public function is_equivalent( self $afe ): bool {
+		if (
+			$this->namespace !== $afe->namespace ||
+			$this->tag_name !== $afe->tag_name ||
+			count( $this->attributes ) !== count( $afe->attributes )
+		) {
+			return false;
+		}
+
+		foreach ( $this->attributes as $name => $value ) {
+			if ( ! array_key_exists( $name, $afe->attributes ) || $value !== $afe->attributes[ $name ] ) {
+				return false;
+			}
+		}
+		return true;
+	}
+
 	public function __construct( string $tag_namespace, string $tag_name, array $attributes, WP_HTML_Token $token ) {
 		$this->namespace  = $tag_namespace;
 		$this->tag_name   = $tag_name;
diff --git a/src/wp-includes/html-api/class-wp-html-processor.php b/src/wp-includes/html-api/class-wp-html-processor.php
index f9e801572a16c..cfcb809abdb93 100644
--- a/src/wp-includes/html-api/class-wp-html-processor.php
+++ b/src/wp-includes/html-api/class-wp-html-processor.php
@@ -6227,7 +6227,6 @@ private function push_active_formatting_element( WP_HTML_Token $token ) {
 		foreach ( $proc->get_attribute_names_with_prefix( '' ) as $name ) {
 			$attributes[ $name ] = $proc->get_attribute( $name );
 		}
-		sort( $attributes );
 		$afe = new AFE_Element(
 			$token->namespace,
 			$token->node_name,