Clickjacking uses a trusted domain or site to trick users into clicking a malicious link. The trusted domain is served in an iframe, then a hidden or transparent UI control is served in the same location. To help protect against this kind of attack, learn more about clickjacking and the Salesforce page types that can be framed. Then review your clickjack settings.
Where: This change applies to Lightning Experience and Salesforce Classic in Contact Manager, Group, Professional, Enterprise, Performance, Unlimited, and Developer editions.