Sec-Fetch-Storage-Access header

The HTTP Sec-Fetch-Storage-Access fetch metadata request header provides the "storage access status" for the current fetch context.

The status can indicate that permission to access unpartitioned third-party cookies:

• Is not granted.
• Has been granted but not activated for the current request context.
• Has been granted for the current request content, and the cookies have been sent with the request.

Supporting browsers must include this header on cross-site requests when the request credential mode is include. The header should not be sent with same-site requests (since those requests cannot involve cross-site cookies), or if the request's credentials mode is "omit". The requested resource must also have a potentially trustworthy origin.

If a storage access permission has been granted but not activated, a server can respond with Activate-Storage-Access to request activation of the permission for the context. For more information see Storage access headers in the Storage Access API overview.