Symbol lookup for methods of objects in container-classes doesn't work

If I have a QList or QMap with QStrings i can use autocompletion on list elements, but I can't use symbol search on the completed methods.

Example:

QList<QString> lst;
lst.first().toUtf8();
	        
QMap<int, QString> map;
map.value(0).toUtf8();

Pressing F2 on toUtf8 does nothing and it is highlighted as normal text.