QtCreator contains hard-coded exceptions for QML types that have run-time defined properties, such as Connections and ListElement. This prevents a warning about invalid property names.

This is not a proper solution. Not only is it wrong (Connections for instance is part of QtQml and not QtQuick), but also does this prevent users from creating their own custom types with such a behavior.

I propose to add a flag "hasDynamicProperties" to the qmltypes file grammar and respect this in QtCreator. See also this forum thread.