The list of release-groups known to FileBot is here:
https://github.com/filebot/data/blob/master/release-groups.txt
The list of recent changes is here:
https://github.com/filebot/data/commits/master/release-groups.txt
Release groups not in this lists will not be recognized by FileBot, so if you stumble across missing release groups post them here and I'll add them to the list. Please post lists of release groups line-by-line with official upper-case/lower-case spelling (e.g. aXXo) so I can easily merge them into the online list. FileBot will update its locally cached release group data from this online list once a week meaning this list is shared with all users.

If you use {group} you will want to make sure that your expression still works as intended even if {group} is undefined. This can easily be done by making the separator characters part of the {expression} code, e.g.
Code: Select all
{'.'+group}
Code: Select all
{n.findMatch(group) ? null : group}
If your files already follow scene naming standards (e.g. "avatar-group.avi") you can try this expression which doesn't rely on a list of known release group names and just matches text patterns:
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{fn.match(/(?<=[-])\w+$/)}