Managing Groups
Check which groups you are in, and which are available:
1groups
2cat /etc/group
3column -ts: /etc/group
4grep $USER !$
Remove yourself from all groups, and add yourself back to only mail, audio, and your own group:
1sudo usermod --groups mail,audio,$USER
Add yourself to the docker group, if there is one:
1grep docker /etc/group
2sudo usermod --append --groups docker $USER
Add yourself to the games group:
1sudo usermod -aG games $USER
You are now legally permitted to play games.
The changes have not taken effect, so log into your own account again with su:
1groups
2grep audio /etc/group
3
4sudo usermod -aG audio $USER
5groups
6grep audio /etc/group
7
8su $USER
9groups
10grep audio /etc/group