diff --git a/public/plugins_packages/core/Blubber/controllers/messenger.php b/public/plugins_packages/core/Blubber/controllers/messenger.php
index 3f857cd5e4abde49be58b20edf5fe6db2b7391f6..8f6a0d2a2fb76b47750cd728ca7516647df24cc3 100644
--- a/public/plugins_packages/core/Blubber/controllers/messenger.php
+++ b/public/plugins_packages/core/Blubber/controllers/messenger.php
@@ -14,7 +14,9 @@ class MessengerController extends PluginController
     {
         PageLayout::setTitle(_("Blubber"));
 
-        Navigation::activateItem("/course/blubber");
+        if (Navigation::hasItem('/course/blubber')) {
+            Navigation::activateItem("/course/blubber");
+        }
 
         $this->threads = BlubberThread::findByContext(Context::get()->id, true, Context::getType());