// qurlquery.h

inline void QUrl::removeAllQueryItems(const QString &key)
{ QUrlQuery q(*this); q.removeAllQueryItems(key); }

inline void QUrl::removeQueryItem(const QString &key)
{ QUrlQuery q(*this); q.removeQueryItem(key); setQuery(q); }

QByteArray const GROUP_NAME = "group";

QUrl url;

url.addQueryItem(GROUP_NAME, "value0");
url.addQueryItem(GROUP_NAME, "value1");

url.removeAllQueryItems(GROUP_NAME); // No one of query items removed here.

qDebug() << url.queryItems().count();