Cubase HiDpi resize Bug?

I may have found a bug with HiDpi in Cubase. Or maybe I am doing something wrong?

My problem: The UI size of our VST3 plugin gets bigger (or smaller) each time our tester opens it in Cubase on a 4k screen on Windows.
My goal: I want the UI size to stay the same.

In Cubase open the “Preferences” menu, then click on “General”. At the top you have the “HiDpi” settings. Make sure “Enable HiDpi” is checked. The below drop-down presents you with several options: “User System Settings”, “+25%”, “+50%”, “-25%” and “-50%”.
As long as I am using “User System Settings” all is fine. But if I choose “-25%” or “50%”, the UI gets a little bigger each time I open it. And if I use “+25%” or “+50%”, the UI gets a little smaller each time.

We can reproduce this behaviour with a simple JUCE test plugin. The plugin is attached. I’ll also attach a video, which shows the problem. In the video you first see the good setting “User System Settings” and afterwards the problematic ones.

We did the test using Cubase 12.0.3, VST3 and JUCE 7.0.2 under Windows.

The test project: (5.2 KB)

The video link: