public static function removeDangerous(string $html) : string
{
static $dangerous = ['~\\s+href="javascript[^"]*"~i', '~\\s+src="javascript[^"]*"~i', '~\\s+href="data:[^"]*"~i', '~\\s+src="data:[^"]*"~i'];
return preg_replace($dangerous, '', $html);
}