When we added a GUI to tl-run-rdesktop it unfortunately got a bit messy as the GUI code is intermixed with the "normal" logic, and we also have to make sure things work even the PyGTK is missing.
Things would probably be cleaner if we separate things like we do for tl-run-xstartup.d.
Fixed in r27811.
Tester should check that all tl-run-rdesktop magic still works. Also check that the GUI is updated properly.
I've tested this as part of all rdesktop bugs, and it seems to work well enough.