When testing 4.19.0rc1 client on rpi4 (Raspbian 12), I was unable to copy-paste out from the session but it worked to copy-paste into the session. This seems to be the due to the Wayland window manager. To circumvent this the window manager was changed to X11 using the provided solution in Bug 8479.
I did some more testing on both RPI4 and RPI5. I have seen copy/paste issues on both platforms and when using both the 4.18.0 ThinLinc client and the 4.19.0 ThinLinc client. In my testing, I only noticed problems when copying INTO the session, not OUT of the session (as described in comment 0). With the 4.18.0 client, I only experienced issues with the primary selection. While with 4.19.0, I also saw issues with the regular clipboard. But things seem so unstable on LabWC that I don't think we can draw any conclusions from that. While I can't really pinpoint when things go wrong, I feel we can conclude that this is not our fault. I only saw issues when using LabWC, both on RPI4 and RPI5. Things worked perfectly when using Wayfire or X11. I also saw differences after upgrading packages, as things actually became more broken after updates. I couldn't pinpoint which package was the culprit (there was no update to LabWC itself).
