diff --git a/chrome/test/index.ts b/chrome/test/index.ts
index 8d0df4336e..3da3f534be 100644
--- a/chrome/test/index.ts
+++ b/chrome/test/index.ts
@@ -210,6 +210,19 @@ function executeScriptFramed () {
     
 }
 
+// for chrome.tabs.TAB_ID_NONE
+function realTabsOnly () {
+    chrome.webRequest.onBeforeRequest.addListener(function (details) {
+        if (details.tabId === chrome.tabs.TAB_ID_NONE) {
+            console.log("Request not related to a tab. %o", details);
+            return;
+        }
+        // ...
+    }, {
+        urls: ["<all_urls>"]
+    });
+}
+
 // contrived settings example
 function proxySettings() {
     chrome.proxy.settings.get({ incognito: true }, (details) => {