I'm connecting a desktop to a laptop which has a 3000*2000 resolution, if I keep this resolution, the reaction of the desktop would be a bit slow, But when I change it to 1920*1080, RDP became a float window(Some shortcut also don't work if I do so). So I want to know if there's a way to decrease the display resolution of RDP connection without shrinking the window.
As far as I remember, you can modify the .rdp file and set the desktop height and width. Here's the link to .rdp options: https://technet.microsoft.com/en-us/library/ff393699(WS.10).aspx
Also try using another RDP, this for example: https://www.donkz.nl