Invalid property name "orientation" (M16) in Design mode

[Bendilock]

Hello,

I am getting an error with QtCreator 5.0.3-2. I have installed qt5 version 5.15.2. I am using Manjaro Xfce21.1.6.

I create an new "Qt Quick Application - Empty", then add a "QtQuick UI File", and open it in Design mode. I drag a rectangle into my Item and press "Fill color" to choose a color. Solid colors work fine, but as soon as I choose Linear, I get an error message saying 'Invalid property name "orientation" (M16)'. I can still choose a color, but nothing gets applied to the rectangle. If I click the Gradient Picker and choose a predefined gradient, I get the same error when clicking Apply, and no colors get applied.

I searched and found posts regarding Invalid Property Name errors, but nothing about the "orientation" property.

Anyone have a clue what the issue might be and how to solve it?

Best regards,
Gustav

[Bendilock]

Update:

If I add the gradient in the Text Editor first, then I can play around with the gradient in the Form Editor just fine! But the predefined gradients in the Gradient Picker still generate the same error.

Best regards,
Gustav