diff --git a/packages/application-extension/src/index.ts b/packages/application-extension/src/index.ts
index 109fd19fc..fac2a0af9 100644
--- a/packages/application-extension/src/index.ts
+++ b/packages/application-extension/src/index.ts
@@ -159,10 +159,12 @@ const opener: JupyterFrontEndPlugin<void> = {
   id: '@retrolab/application-extension:opener',
   autoStart: true,
   requires: [IRouter, IDocumentManager],
+  optional: [ISettingRegistry],
   activate: (
     app: JupyterFrontEnd,
     router: IRouter,
-    docManager: IDocumentManager
+    docManager: IDocumentManager,
+    settingRegistry: ISettingRegistry | null
   ): void => {
     const { commands } = app;
 
@@ -178,9 +180,12 @@ const opener: JupyterFrontEndPlugin<void> = {
 
         const file = decodeURIComponent(path);
         const ext = PathExt.extname(file);
-        app.restored.then(() => {
+        app.restored.then(async () => {
           // TODO: get factory from file type instead?
           if (ext === '.ipynb') {
+            // TODO: fix upstream?
+            await settingRegistry?.load('@jupyterlab/notebook-extension:panel');
+            await Promise.resolve();
             docManager.open(file, NOTEBOOK_FACTORY, undefined, {
               ref: '_noref'
             });