When a user clicks on the Communicate workaround UI action on the Problem form, what happens?
When you communicate a fix, notification is sent to related incidents that a fix is available. The Incident process is designed to use the fix information or to notify the user of the same.
https://www.servicenow.com/docs/bundle/yokohama-it-service-management/page/product/problem-management/task/communicate-a-fix.html