diff --git a/src/views.ts b/src/views.ts
index cfa23d2..bc3b3d6 100644
--- a/src/views.ts
+++ b/src/views.ts
@@ -906,6 +906,9 @@ class AddonViews extends AddonBase {
     const _window = this._Addon.knowledge.workspaceTabId
       ? window
       : this._Addon.knowledge.getWorkspaceWindow();
+    if (!_window) {
+      return;
+    }
     Zotero.debug("updateWordCount");
 
     const menuitem = _window.document.getElementById(