diff --git a/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-agents.js b/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-agents.js
index 9c53f21969ffd..c377f5dfe0d91 100644
--- a/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-agents.js
+++ b/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-agents.js
@@ -15,7 +15,7 @@
 
   TestRunner.addSniffer(SDK.MainConnection.prototype, 'sendRawMessage', function(messageString) {
     var message = JSON.parse(messageString);
-    if (!message.sessionId)
+    if (!message.sessionId || message.sessionId === SDK.targetManager.mainFrameTarget().sessionId)
       return;
     if (messageString.includes('DOM.'))
       TestRunner.addResult('DOM-related command should NOT be issued: ' + messageString);
diff --git a/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-manager.js b/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-manager.js
index 6bcf5cde963c5..d3d19d3b9c34b 100644
--- a/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-manager.js
+++ b/third_party/blink/web_tests/http/tests/devtools/service-workers/service-worker-manager.js
@@ -18,7 +18,7 @@
     targetAdded: function(target) {
       TestRunner.addResult('Target added: ' + target.name() + '; type: ' + target.type());
       if (target.type() === SDK.Target.Type.ServiceWorker) {
-        var serviceWorkerManager = SDK.targetManager.mainTarget().model(SDK.ServiceWorkerManager);
+        var serviceWorkerManager = SDK.targetManager.mainFrameTarget().model(SDK.ServiceWorkerManager);
         // Allow agents to do rountrips.
         TestRunner.deprecatedRunAfterPendingDispatches(function() {
           for (var registration of serviceWorkerManager.registrations().values())