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function is not described

wp_favicon_request() WP 3.0.0

Deprecated from version 5.4.0 Deprecated in favor of do_favicon().. It is no longer supported and can be removed in future releases. It is recommended to replace this function with the same one.

Don't load all of WordPress when handling a favicon.ico request.

Instead, send the headers for a zero-length favicon and bail.

No Hooks.

Return

````. Null. Nothing.

Usage

wp_favicon_request();

Changelog

Since 3.0.0 Introduced.
Deprecated Since 5.4.0 Deprecated in favor of do_favicon().

Code of wp_favicon_request() WP 5.7

<?php
function wp_favicon_request() {
	if ( '/favicon.ico' === $_SERVER['REQUEST_URI'] ) {
		header( 'Content-Type: image/vnd.microsoft.icon' );
		exit;
	}
}