Comment # 1 on bug 1041499 from Pieter Hollants

Further up in the strace output it seems that the auth information read in from
/home/pief/.Xauthority is rejected:

  recvfrom(5, "\0\26\v\0\0\0\6\0", 8, 0, NULL, NULL) = 8
recvfrom(5, "No protocol specified\n\0\0", 24, 0, NULL, NULL) = 24

Explaining why it falls back to trying broadwayd.

But why is it rejected? I tried removing /home/pief/.Xauthority and relogin,
but that didn't help of course.

(Note that I do NOT have a ~/.Xinitrc and
/etc/X11/xinit/xinitrc.d/50-systemd-user.sh appears to run correctly.)