diff --git a/js/dbusServices/extensions/extensionPrefsDialog.js b/js/dbusServices/extensions/extensionPrefsDialog.js
index 9e3ea57ee..6e6b4c8ce 100644
--- a/js/dbusServices/extensions/extensionPrefsDialog.js
+++ b/js/dbusServices/extensions/extensionPrefsDialog.js
@@ -38,7 +38,7 @@ export const ExtensionPrefsDialog = GObject.registerClass({
         const prefsObj = new prefsModule.default({...metadata, dir, path});
         this._extension.stateObj = prefsObj;
 
-        prefsObj.fillPreferencesWindow(this);
+        await prefsObj.fillPreferencesWindow(this);
 
         if (!this.visible_page)
             throw new Error('Extension did not provide any UI');
diff --git a/js/extensions/prefs.js b/js/extensions/prefs.js
index f36b97138..76ae3ca62 100644
--- a/js/extensions/prefs.js
+++ b/js/extensions/prefs.js
@@ -18,7 +18,7 @@ export class ExtensionPreferences extends ExtensionBase {
      * Get the single widget that implements
      * the extension's preferences.
      *
-     * @returns {Gtk.Widget}
+     * @returns {Gtk.Widget|Promise<Gtk.Widget>}
      */
     getPreferencesWidget() {
         throw new GObject.NotImplementedError();
@@ -31,9 +31,10 @@ export class ExtensionPreferences extends ExtensionBase {
      * returned by getPreferencesWidget().
      *
      * @param {Adw.PreferencesWindow} window - the preferences window
+     * @returns {Promise<void>}
      */
-    fillPreferencesWindow(window) {
-        const widget = this.getPreferencesWidget();
+    async fillPreferencesWindow(window) {
+        const widget = await this.getPreferencesWidget();
         const page = this._wrapWidget(widget);
         window.add(page);
     }