diff --git a/js/extensions/prefs.js b/js/extensions/prefs.js
index d60859a3d..f36b97138 100644
--- a/js/extensions/prefs.js
+++ b/js/extensions/prefs.js
@@ -1,3 +1,4 @@
+import Adw from 'gi://Adw';
 import GObject from 'gi://GObject';
 
 import {ExtensionBase, GettextWrapper} from './sharedInternals.js';
@@ -13,13 +14,45 @@ export class ExtensionPreferences extends ExtensionBase {
         return wrapper.defineTranslationFunctions();
     }
 
+    /**
+     * Get the single widget that implements
+     * the extension's preferences.
+     *
+     * @returns {Gtk.Widget}
+     */
+    getPreferencesWidget() {
+        throw new GObject.NotImplementedError();
+    }
+
     /**
      * Fill the preferences window with preferences.
      *
-     * @param {Adw.PreferencesWindow} _window - the preferences window
+     * The default implementation adds the widget
+     * returned by getPreferencesWidget().
+     *
+     * @param {Adw.PreferencesWindow} window - the preferences window
      */
-    fillPreferencesWindow(_window) {
-        throw new GObject.NotImplementedError();
+    fillPreferencesWindow(window) {
+        const widget = this.getPreferencesWidget();
+        const page = this._wrapWidget(widget);
+        window.add(page);
+    }
+
+    _wrapWidget(widget) {
+        if (widget instanceof Adw.PreferencesPage)
+            return widget;
+
+        const page = new Adw.PreferencesPage();
+        if (widget instanceof Adw.PreferencesGroup) {
+            page.add(widget);
+            return page;
+        }
+
+        const group = new Adw.PreferencesGroup();
+        group.add(widget);
+        page.add(group);
+
+        return page;
     }
 }