Permissions-Policy: loopback-network directive

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The HTTP Permissions-Policy header loopback-network directive controls whether the current document is allowed to make network requests to loopback addresses.

A loopback address is only accessible on the local host; its target will differ on every device. For example, 127.0.0.1, which is generally known as localhost.

Specifically, where a defined policy blocks use of this feature, requests to loopback addresses will always fail.

See Local Network Access for more details.

Syntax

http
Permissions-Policy: loopback-network=<allowlist>;
<allowlist>

A list of origins for which permission is granted to use the feature. See Permissions-Policy > Syntax for more details.

Default policy

The default allowlist for loopback-network is self.

Specifications

This feature does not appear to be defined in any specification.

Browser compatibility

See also