Replicated the issue as described by the customer

1. Go to confluence page and create a comment. Add @ and see that the guest user will be available in the suggestion list
2. Now use the share function and try to share the page with the guest user
   1. → you won’t find the user in the suggestion list
   2. → when typing in the E-Mail of that user Confluence will state that he has no permission and needs to be invited first

Expected Results

It should display the guest when you search for their name from the share button.

Actual Results

It does not display the guest when you search for their name through share button.