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Log in as a user with the 'Jira Administrators' global permission.
Navigate to Admin menu → Manage apps → Communities.
Go to the Product Setting page.
Enable desired functionality → press Save.
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Public Access
When Public access is enabled, external users will be able to self-register and create an account in Jira Internal Directory. Those users will not have access to your Jira instance and DO NOT count towards your license limit.
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