RDP-backend reports extremely large monitor sizes

This is due to RDP-backend simply setting the output physical size in millimeters to the output resolution in pixels, leading to 1 px/mm or 25.4 PPI. Applications that actually look at this number will be rendered unreadable. My use case is claws-mail which is a GTK+ 2 app running via Xwayland, and I am only guessing this is the reason why the fonts are roughly 5 pixels tall.

If there is no other information available, assume e.g. 96 PPI and compute the physical size from resolution using that.

If you can figure out the physical desktop size on a remote via FreeRDP API, that would be cool too, but not required.