If a tester cannot see the Create Known Error article link, what might be the issue?

The reason the selected answer is appropriate is that the Problem Management Best Practice - Madrid - Knowledge Integration plugin includes essential functionalities related to Knowledge Management, specifically the creation of Known Error articles. If this plugin has not been activated, the features associated with it, such as the ability to create or view links for Known Error articles, will not be accessible to users, including testers.

For a tester to see the Create Known Error article link, they must have the correct configurations and implementations in place, which include having the necessary plugins activated. Without this particular plugin, even if other prerequisites (like roles or impersonation) are met, the functionality itself simply won't be available.

Impersonation restrictions or role requirements are indeed important aspects of visibility in a system, but if the underlying plugin that facilitates that functionality is not activated, those roles and impersonation settings will be irrelevant since the basic capability does not exist. Therefore, activating the specific plugin is crucial for ensuring that the tester can see the necessary links related to Known Error articles.