change some comments in the code as per review comment

packages/react-devtools-extensions/src/background.js

@@ -99,16 +99,19 @@ if (!IS_FIREFOX) {
   );
 }
 
+// Listen to URL changes on the active tab and update the DevTools icon.
 chrome.tabs.onUpdated.addListener((tabId, changeInfo, tab) => {
-  // Listen to URL changes on the active tab and reset the DevTools icon.
-  // This prevents non-disabled icons from sticking in Firefox.
-  // Don't do this in Chrome or Edge though.
-  // It fires more frequently, often after onMessage() has been called.
   if (IS_FIREFOX) {
+    // We don't properly detect protected URLs in Firefox at the moment.
+    // However we can reset the DevTools icon to its loading state when the URL changes.
+    // It will be updated to the correct icon by the onMessage callback below.
     if (tab.active && changeInfo.status === 'loading') {
       setIconAndPopup('disabled', tabId);
     }
   } else {
+    // Don't reset the icon to the loading state for Chrome or Edge.
+    // The onUpdated callback fires more frequently for these browsers,
+    // often after onMessage has been called.
     checkAndHandleRestrictedPageIfSo(tab);
   }
 });