When a developer assigns a RadialGradient to a Rectangle, for example, as background fill, then the QMLLInter posts the following warning:
"Warning: /var/folders/7q/0ftm5_g54b91ck89ym4wjycr0000gp/T/tmp49y2_mlh.qml:19:9: RadialGradient was not found. Did you add all imports and dependencies? [import]
        RadialGradient

Gradient {{*}"

The suggestion to use a Gradient instead of RadialGradient is unlikely to correspond to the user's intention because the user has already taken the effort to define a RadialGradient. Would it be more helpful to indicate to the user that "RadialGradient can only be used with QML type Shape"?