--- a/browser/components/extensions/test/browser/browser_ext_tabs_onUpdated.js
+++ b/browser/components/extensions/test/browser/browser_ext_tabs_onUpdated.js
@@ -25,17 +25,21 @@ add_task(function* () {
       let expectedSequence = [
         {status: "loading"},
         {status: "loading", url: pageURL},
         {status: "complete"},
       ];
       let collectedSequence = [];
 
       browser.tabs.onUpdated.addListener(function(tabId, updatedInfo) {
-        collectedSequence.push(updatedInfo);
+        // onUpdated also fires with updatedInfo.faviconUrl, so explicitly
+        // check for updatedInfo.status before recording the event.
+        if ("status" in updatedInfo) {
+          collectedSequence.push(updatedInfo);
+        }
       });
 
       browser.runtime.onMessage.addListener(function() {
         if (collectedSequence.length !== expectedSequence.length) {
           browser.test.assertEq(
             JSON.stringify(expectedSequence),
             JSON.stringify(collectedSequence),
             "got unexpected number of updateInfo data"