add_action('http_api_debug', function($response, $context, $class, $args, $url) {
    if (empty($_GET['izperf']) || $_GET['izperf'] !== 'check2026') return;

    static $last = null;
    $now = microtime(true);

    error_log('IZHTTP '.json_encode(array(
        'url'=>$url,
        'at'=>round($now-$GLOBALS['izperf_start'],3),
        'since_previous'=>$last === null
            ? null : round($now-$last,3)
    )));

    $last = $now;
}, 10, 5);

add_action('http_api_debug', function($response,$context,$class,$args,$url) {
 if (($_GET['izperf'] ?? '') === 'check2026')
  error_log('IZHTTP '.round(microtime(true)-$GLOBALS['izperf_start'],3).' '.esc_url_raw($url));
},10,5);
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