diff --git a/addon/chrome/content/workspaceWindow.xhtml b/addon/chrome/content/workspaceWindow.xhtml
index 70f0a59..6a7c149 100644
--- a/addon/chrome/content/workspaceWindow.xhtml
+++ b/addon/chrome/content/workspaceWindow.xhtml
@@ -66,6 +66,9 @@
     </style>
   </head>
   <body class="zotero-window workspace-window">
+    <xul:popupset>
+      <xul:tooltip id="html-tooltip" page="true" />
+    </xul:popupset>
     <div id="workspace-container"></div>
   </body>
 </html>
