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Log in as a user with the 'Jira Administrators' global permission.
Navigate to Admin menu → Issues → Custom fields → locate Group picker field.
Go to Actions → Configure → click Edit Groups++ custom field.
Select which attributes will be visible in Layout section.
Add rules (optional).
Layout
Layout section consists of the following columns:
Name of added attributes.
Display name - allows defining which attribute will be displayed in a group name (only for text attributes).
Visible in edit - allows defining attribute's visibility on the Edit screen.
Visible in preview - allows defining attribute's visibility on the Issue screen.
Group picker field rules
You can define a condition based on any added attribute or membership in any group (Reported / Assignee / Current user in group).
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