When I enter "who" as below, only tty2 appears, and the local display does not show up:
team@pc1:~$ who
team tty2 2024-04-09 15:06 (tty2)
team pts/0 2024-04-09 15:06 (111.111.111.111)
On other computers, the DISPLAY environment variable value ":0" appeared in the "who" command like below:
team@pc2:~$ who
team :0 2024-04-09 16:23 (:0)
team pts/0 2024-04-09 16:23 (111.111.111.111)