User selection in mentioning, restrictions, permissions
Confluence works differently than Jira in the case of licensed or not licensed users. Confluence itself restricts some functionality for unlicensed users, and there is no known workaround for this currently.
Licence Optimizer for Confluence should be configured as the Access group is added to the “Licensed users” Global Permission in Confluence administrator settings with “can use” enabled. This is the most basic permission that allows users to log in to this Confluence site. Users with this permission contribute to your licensed users count.
The problem is, that users that do not belong to any "can-use" permission are “invisible” for Confluence and some features that work with users are not available.
Some features are:
restricting space or page
mention a user
select in macro
etc.
Mobile view
License Optimizer will continue to work when the users log in to the app via smartphone. However, in this case, the users won’t get a warning message about their revoked access.
Jira Macros and linked Confluence pages
If the logged-in user does not have a valid license currently (since LO removed the user from the group) in either Jira or Confluence, macros or links will not be displayed.