$query = [
'returnto' => $this->getFullTitle()->getPrefixedDBkey(),
'returntoquery' => wfArrayToCgi( array_diff_key( $request->getQueryValues(),
$query = [
'returnto' => $this->getFullTitle()->getPrefixedDBkey(),
'returntoquery' => wfArrayToCgi( array_diff_key( $request->getQueryValues(),