Include Link response headers for agent discovery (RFC 8288)

Thank you for reporting this and for your patience.

We’ve identified the issue and implemented a fix. To resolve it on your end, please update the code in execute-cache.php (around line 662) with the following:

$sent_headers = array();
foreach ( $datas['headers'] as $data ) {
$lower_name = strtolower( $data['name'] );
$replace = ! isset( $sent_headers[ $lower_name ] );
header( $data['name'] . ': ' . $data['value'], $replace );
$sent_headers[ $lower_name ] = true;
}

This ensures that response headers (including Link headers for agent discovery as per RFC 8288) are handled correctly without duplication issues.

We will also include this fix in an upcoming plugin release so you won’t need to apply it manually in the future.

Please let us know if you need any further assistance or if the issue persists after applying the fix.