VST3 SDK editorhost displays only 25% of JUCE GUI on 4k Monitor

I am trying to write a VST3 host.
I can’t get plugin GUIs to show at the correct size on my 4k monitor. They are truncated/clipped.

So I built the VST3 SDK example ‘editorhost’ from the current latest SDK, and attempted to load a JUCE plugin. It displays at 50% of the height and 50% of the width that I expected. i.e. I can only see the top-left quarter of the UI.

My expected outcome is that the window dimensions are twice this, and that I can see and interact with the entire GUI.

My monitor dimensions are 4500x3000 and my scaling is set to 200% on Windows 10.

any hints appreciated.

Have you tried one of the included examples in the SDK? The AGain example has a UI made with VSTGUI. Does it come up correctly?