I have 2 displays (:0 and :1) on OTHER_HOST. I run:
$ xpra shadow ssh:OTHER_HOST:1 [...] too many live X11 displays to choose from: :0, :1 [...]
Expected: the command should shadow display :1 on OTHER_HOST
Patch to fix
FYI: the 0.17.x branch is already EOL, see wiki/Versions, and this bug had already been fixed in v1.0
Well done finding the correct fix for v0.17.x though!
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/1395