The fullscreen policy controls whether the requestFullscreen() method is allowed to request fullscreen.

If disallowed in any document, the document will not be allowed to use fullscreen. Triggering full-screen mode can be a jarring experience for users, and can be exploited by content that would otherwise be confined to a small frame.

How to apply this policy

Send the following HTTP header to control the fullscreen policy, and disallow it on all origins:

Feature-Policy: fullscreen 'none'

Does it work?

Currently Firefox, and Chromium based browsers, such as Google Chrome, Samsung Internet, and Opera, are the only user-agents to support Feature Policy. The minimum version that correctly recognises the fullscreen policy is:

Mozilla Firefox


Google Chrome


Microsoft Edge

Not supported

Apple Safari

Not supported


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