How to use Content Security Policy (CSP) against clickjacking?

The option is to use Content Security Policy (CSP) and its frame-ancestors directive. This directive allows the application developer to disallow all frame use or specify where it is allowed, similar to X-Frame-Options.

Possible CSP frame-ancestor settings:

• Content-Security-Policy: frame-ancestors ‘none’
• Content-Security-Policy: frame-ancestors ‘self’
• Content-Security-Policy: frame-ancestors example.com