public function toggleFramed( $framed = null ) {
		$this->framed = $framed !== null ? (bool)$framed : !$this->framed;
		$this->toggleClasses( [ 'oo-ui-buttonElement-framed' ], $this->framed );
		$this->toggleClasses( [ 'oo-ui-buttonElement-frameless' ], !$this->framed );
		return $this;
	}