Hey Gleb, I took a look at your logs and it appears that you have a separate client capability issue.
The patch gets KRDP past PAM and portal/session startup and was able to init the video encoder in your log: 2026-06-09T19:10:29.346561+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: Initializing Freedesktop Portal Session 2026-06-09T19:10:29.359159+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: Session setup completed, start processing... 2026-06-09T19:10:29.394472+03:00 user-virtualbox kded6[1702]: Registering ":1.61/StatusNotifierItem" to system tray 2026-06-09T19:10:29.469814+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: Started Freedesktop Portal session 2026-06-09T19:10:31.366619+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: New client connected: UNIX platform Unspecified version 2026-06-09T19:10:31.366662+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: Attempting authenticating user with PAM 2026-06-09T19:10:31.483852+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: PAM authentication succeeded for user "user" 2026-06-09T19:10:31.484555+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: Video stream initialized However, it fails when negotiating RDPGFX: 2026-06-09T19:10:31.508277+03:00 user-virtualbox krdpserver[1818]: org.kde.krdp: Client does not support H.264 in YUV420 mode! This is a different issue from mine due to your client advertises AVC on one capset and YUV420 on other capsets, but not both together, so KRDP closes the session with ERRINFO_GRAPHICS_SUBSYSTEM_FAILED. A full fix might be able to be obtained from upstream KRDP code in the commits around: b879acb Progressive encoding support f9cd667 Dynamically switch between progressive and h264 based on capabilities But backporting those patches is a bit more involved. Maybe try a different client to see if you have better luck with this version? I had good success with MSRDP from Windows 11. If you are connecting from another Linux host, maybe see if a newer FreeRDP or Remmina client is available that has support for H264/RDPGFX AVC420? Hope this helps, Rob -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2141392 Title: Black screen and disconnect in rdp client To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/krdp/+bug/2141392/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
