Hello.
Since you are here, you are having trouble accessing your PGAdmin container that you created with docker and one of the reasons is this writing error.
Lets read the error first, if you came here by luck and dont know what causes you to cant access your pgadmin container lets try writing docker logs <container with pgadmins id> to our terminal first.
[2025-04-06 11:17:23 +0000] [502] [INFO] Worker exiting (pid: 502)
HINT Create the directory /var/lib/pgadmin/sessions, ensure it is writeable by 'pgadmin', and try again, or, create a config_local.py file and override the SESSION DB PATH setting per https://www.pgadmin.org/docs/pgadmin4/9.2/config.py.html
[Errno 13] Permission denied: '/var/lib/pgadmin/sessions'