bug#21349: who shows no users nowadays on Debian

[積丹尼 Dan Jacobson]

(info "(coreutils) who invocation") says

If given no non-option arguments, ‘who’ prints the following
information for each user currently logged on: login name, terminal
line, login time, and remote hostname or X display.

Say if this means
remote hostname or remote X display.

or

X display or remote hostname.

By the way, now on Debian sid:

$ who
$ ps a
  PID TTY      STAT   TIME COMMAND
  593 tty7     Ss+    0:10 /usr/lib/xorg/Xorg :0 -nolisten tcp vt7
 1310 pts/0    Ss     0:00 bash
 1338 pts/1    Ss     0:00 su -
 1339 pts/1    S+     0:00 -su
 2005 tty1     Ss+    0:00 /sbin/agetty --noclear tty1 linux
 2073 pts/0    R+     0:00 ps a