Ticket #64567: 64567-fix.patch.patch

src/wp-includes/html-api/class-wp-html-tag-processor.php

@@ -1716 +1716 @@
          * @return string[] List of attribute names.
          */
         public function get_attribute_names_with_prefix( $prefix ) {
-                return array_keys( $this->attributes );
+                $attribute_names = array();
+
+                // Include parsed attributes.
+                foreach ( $this->attributes as $name => $_value ) {
+                        if ( str_starts_with( $name, $prefix ) ) {
+                                $attribute_names[ $name ] = true;
+                        }
+                }
+
+                // Include enqueued attribute updates.
+                foreach ( $this->updated_attributes as $name => $value ) {
+                        if ( null === $value ) {
+                                unset( $attribute_names[ $name ] );
+                                continue;
+                        }
+
+                        if ( str_starts_with( $name, $prefix ) ) {
+                                $attribute_names[ $name ] = true;
+                        }
+                }
+
+                return array_keys( $attribute_names );
         }
 }