It's okay to send the text on stderr, when invalid option is given:
But not, when help is asked:
/usr/bin/Xephyr --help | less
Please change the -help option to send text to stdout, not stderr.
See GNU cp(1), ls(1) etc. for reference.
This appears to be a problem with the X server in general, not just Xephyr. The function for printing the help message can be found at  and as you can see it writes everything to stderr regardless of the situation. It is called by both the normal X server and Xephyr.
Perhaps this should be reopened as a general X server issue?
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