Permissions-Policy: midi directive

The HTTP Permissions-Policy header midi directive controls whether the current document is allowed to use the Web MIDI API.

Specifically, where a defined policy blocks use of this feature, Navigator.requestMIDIAccess() calls will return a Promise that rejects with a DOMException of type NotAllowedError.

Syntax

Permissions-Policy: midi=<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 midi is self.

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Reason: CORS header 'Access-Control-Allow-Origin' does not match 'xyz

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Content Security Policy: The page's settings blocked the loading of a resource: xyz

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