I have added this issue to the tracker:
Issue 2288 – Tree indentation does not scale correctly

Yes, the primary is the native notebook display with 4K (3840x2160) res and 200% scaling for text etc., the two external are set to 1920x1200.

Thanks. Though I'm not able to reproduce the problem anyway.
Is that Windows 11?
Which display is the primary one? The notebook lid or one of the externals?
Is it the notebook lid that has higher density? Is it 200% scaling?

Hi Martin

Yes, I use 2 external monitors connected via docking station to notebook and the primary has different resolution. When I drag and move the application to the primary monitor it looks good, like you have posted. When I drag it back to the external monitor, it is bad again.

Robert

That's not how the tree should look like.
See https://winscp.net/eng/docs/ui_explorer

Anything unusual about your system? Don't you have multiple displays? What are their settings? Can you post screenshots from System > Display in Windows Settings?

Add option to define the horizontal skip (number of dots) for a subfolder from its parent in Tree view. Now there are approximately 10 dots and that makes the tree very wide.