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This feature is available in Live Forms v4.1.4 and higher. You can specify a Confluence group here. If specified, users belonging to this group can edit forms and flows already added to existing Confluence pages belonging to any other user. If this is set to No Group, edit access is restricted to the original designer/owner of the form/flow. Users belonging to this group can also view/delete submissions for forms and flows belonging to any other user. Note that the editor also needs to have "designer" privileges for this.
This group does not give users permission to create new Confluence pages and add existing forms/flows created by another designer. The only forms you will see in the add existing form dropdown are the forms created by you.
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