diff --git a/html/cross-origin-opener-policy/reporting/resources/dispatcher.js b/html/cross-origin-opener-policy/reporting/resources/dispatcher.js
index ade25ee15327a4..5a842d03e6e1ad 100644
--- a/html/cross-origin-opener-policy/reporting/resources/dispatcher.js
+++ b/html/cross-origin-opener-policy/reporting/resources/dispatcher.js
@@ -19,13 +19,13 @@ const send = function(uuid, message) {
 
 const receive = async function(uuid, maybe_timeout) {
   const timeout = maybe_timeout || Infinity;
-  const retry_delay = 100;
-  for(let i = 0; i * retry_delay < timeout; ++i) {
+  let start = performance.now();
+  while(performance.now() - start < timeout) {
     let response = await fetch(dispatcher_url + `?uuid=${uuid}`);
     let data = await response.text();
     if (data != 'not ready')
       return data;
-    await new Promise(r => step_timeout(r, retry_delay));
+    await new Promise(r => setTimeout(r, 100)); // Save resources.
   }
   return "timeout";
 }
diff --git a/html/cross-origin-opener-policy/reporting/resources/executor.html b/html/cross-origin-opener-policy/reporting/resources/executor.html
index e97e18aca4bd6f..9f38ebe2159219 100644
--- a/html/cross-origin-opener-policy/reporting/resources/executor.html
+++ b/html/cross-origin-opener-policy/reporting/resources/executor.html
@@ -1,4 +1,3 @@
-<script src=/resources/testharness.js></script>
 <script src="./dispatcher.js"></script>
 <script src="./try-access.js"></script>
 <script>
diff --git a/lint.ignore b/lint.ignore
index 8431077e6a677d..2f8320f819225c 100644
--- a/lint.ignore
+++ b/lint.ignore
@@ -306,6 +306,7 @@ SET TIMEOUT: html/cross-origin-embedder-policy/resources/navigate-none.sub.html
 SET TIMEOUT: html/cross-origin-embedder-policy/resources/navigate-require-corp.sub.html
 SET TIMEOUT: html/cross-origin-embedder-policy/resources/navigate-require-corp-same-site.sub.html
 SET TIMEOUT: html/cross-origin-embedder-policy/resources/reporting-worker.js
+SET TIMEOUT: html/cross-origin-opener-policy/reporting/resources/dispatcher.js
 SET TIMEOUT: html/dom/documents/dom-tree-accessors/Document.currentScript.html
 SET TIMEOUT: html/webappapis/timers/*
 SET TIMEOUT: orientation-event/resources/orientation-event-helpers.js