Cannot create sessions above 1920x1080 on xrdpdev driver for xorg

[NunoHiggs]

Hello all,

I am unable to create an rdp session over 1920x1080 using the xrdpdev driver on x.org.
I have a 4k display, working in 4k, and the biggest session i can launch on rdp with any client, remmina, freerdp,etc, is a 1920x1080 session.

Via console, to the server, i can raise a 4k session with no issue, so it appears the issue is related to the rdp driver.
I have added for testing purposes, another monitor/screen configuration to /etc/X11/xrdp/xorg.conf - the 2560x1440 one - and the problem remains:

Section "Monitor"
    Identifier "Monitor"
    Option "DPMS"
    HorizSync 30-80
    VertRefresh 60-75
    # 2560x1440 @ 60.00 Hz (GTF) hsync: 89.40 kHz; pclk: 311.83 MHz
    Modeline "2560x1440"  311.83  2560 2744 3024 3488  1440 1441 1444 1490  -HSync +Vsync
    ModeLine "1920x1080" 138.500 1920 1968 2000 2080 1080 1083 1088 1111 +hsync -vsync
    ModeLine "1280x720" 74.25 1280 1720 1760 1980 720 725 730 750 +HSync +VSync
    Modeline "1368x768" 72.25 1368 1416 1448 1528 768 771 781 790 +hsync -vsync
    Modeline "1600x900" 119.00 1600 1696 1864 2128 900 901 904 932 -hsync +vsync
EndSection

Section "Device"
    Identifier "Video Card (xrdpdev)"
    Driver "xrdpdev"
    Option "DRMDevice" "/dev/dri/renderD128"
    Option "DRI3" "1"
EndSection

Section "Screen"
    Identifier "Screen (xrdpdev)"
    Device "Video Card (xrdpdev)"
    Monitor "Monitor"
    DefaultDepth 24
    SubSection "Display"
        Depth 24
        Modes "640x480" "800x600" "1024x768" "1280x720" "1280x1024" "1600x900" "1920x1080" "2560x1440"
    EndSubSection
EndSection

For this specific event when i boot the connection it tries to throttle up to 2560x1440, but as soon as it passes the sddm login, it throttles down to 1920x1080:

What am i missing here? All my rdp client configurations run well for windows boxes, at the highest resolution my rdp client can handle.

[matt335672]

That suggests your desktop is hard-wiring the connection size.

Set up a different account for testing and see if that behaves the same way.