Ticket #22543: 22543-1.diff

wp-includes/class-wp-image-editor-imagick.php

@@ -89 +89 @@
                                 return new WP_Error( 'invalid_image', __('File is not an image.'), $this->file);
 
                         // Select the first frame to handle animated GIFs properly
-                        $this->image->setIteratorIndex(0);
+                        if( is_callable( $this->image, 'setIteratorIndex' ) )
+                                $this->image->setIteratorIndex(0);
+
                         $this->mime_type = $this->get_mime_type( $this->image->getImageFormat() );
                 }
                 catch ( Exception $e ) {