Group naming restrictions / guidelines

[Vandersteen]

I've just wasted quite some time figuring out that a '/' is not allowed in group names.
I've been searching, and I can't find any limitations / restrictions / rules / guidelines regarding group names anywhere.

• Max length?
• Allowed chars
• ...

Please advice

[vicancy]

The only limitation for group name is "Valid group name should be in between 1 and 1024 characters long.", what error do you meet when you have / in your group name?