Issue #2969720: Update page title with unread thread count

js/private_message_notification_block.js

@@ -38,6 +38,32 @@ Drupal.PrivateMessageNotificationBlock = {};
     }
 
     notificationWrapper.find(".private-message-page-link").text(unreadThreadCount);
+
+    // Get the current page title.
+    var pageTitle = $("title").text();
+    // Check if there are any unread threads.
+    if (unreadThreadCount) {
+      // Check if the unread thread count is already in the page title.
+      if (pageTitle.match(/^\(\d+\)\s/)) {
+        // Update the unread thread count in the page title.
+        pageTitle = pageTitle.replace(/^\(\d+\)\s/, "(" + unreadThreadCount + ") ");
+      }
+      else {
+        // Add the unread thread count to the URL.
+        pageTitle = "(" + unreadThreadCount + ") " + pageTitle;
+      }
+    }
+    // No unread messages.
+    else {
+      // Check if thread count currently exists in the page title.
+      if (pageTitle.match(/^\(\d+\)\s/)) {
+        // Remove the unread thread count from the page title.
+        pageTitle = pageTitle.replace(/^\(\d+\)\s/, "");
+      }
+    }
+
+    // Set the updated title.
+    $("title").text(pageTitle);
   }
 
   /**