How Do I Update the Group a Custom Field Picks From?

[TimROC]

I am simply trying to update a custom field. It is currently set as a Group Picker (multiple groups). There is a new group I need to add to the picker field. However, I see no way to do this. If I go under Work Items>Fields, I see the custom field, but the edit option does not give me the current list of groups so I cannot add to it. If I go to contexts and default values, I could add the new group as the default value, but it's not the default value. Thanks to all the UI changes, all the "help" articles I've found online are useless since the path(s) they offer no longer exist. I feel this is a simple ask so why does this feel so complicated? I'm looking for help as this has become entirely too frustrating. Thank you.

[Mikael Sandberg]

You do not have to add new groups to a group picker fields, it will be populated by the groups you created on your Atlassian Instance, sort of similar to how user picker fields works (example reporter and assignee).

[TimROC]

This group picker does not show all the groups. It only shows a handful. That's where the confusion is coming in.