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To add a resource that is not a Jira Confluence user, one can consider typing its name in "Choose resource" search field (1). After that you need to click on the below shown "Create new resource name" (2) and click "Add" button (3). Any listed resource can be edited and deleted after clicking triple dot button (4).
Resources that are not Jira Confluence users (they can be calssified classified as external ones - those are all added using the above mentioned and illustrated method) can be find on the final page(s) (5).
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