I'm running the Dropbox Desktop App (64.3.123) on Windows 10 (v1809) laptop.
The one-screen scenario (laptop not connected to the external monitor, so only one HiDPI screen set to 150% scaling) works fine, the app window displays scaled to the 150% the laptop screen is set to.
The issue now arises, when I connect the external monitor, which has the normal resolution of 96 DPI and scaling at 100%. I have set my system to set the external monitor to be the primary monitor, once it is connected. Therefore the Dropbox app window is displayed on the external monitor, but it continues to be scaled to 150%. This is obviously too large.
I assume that the Desktop App does not support per-monitor scaling. Is this an issue that can be fixed? Or is there a workaround?