Currently requires manual patching. We either have to bundle another module (distribute?) or just patch the thing. (skipping rant about why we need a whole module to get the version number)
@smo: did you resolve the other lz4 issue you had?
AFAICT, the import issue is fixed, see #1929
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/1986