Can't open or create Design Effects in Creator

1. Use online installer to install "Developer tools" and "Designer tools" on Mac.
2. Run Qt Design Studio.
3. Create a simple QML file with a Rectangle with an effect on it.
4. Choose File > Export Project > Enable Automatic CMake Generation.
5. Close Qt Design Studio, Run Qt Creator.
6. Open the project.
7. Try to edit the QML file. You get an error about QtQuick.Studio.DesignEffects.
8. If you make a clean QML file in Creator and try to add an effect in design mode, you also get an error about QtQuick.Studio.DesignEffects.

Seems like Design Studio has the DesignEffect components/libraries installed, but Creator does not.