diff --git a/extension.js b/extension.js
index 0bed3e4..5ce2cbf 100644
--- a/extension.js
+++ b/extension.js
@@ -24,13 +24,18 @@ import Meta from 'gi://Meta';
 import Shell from 'gi://Shell';
 import St from 'gi://St';
 
-import {Extension} from 'resource:///org/gnome/shell/extensions/extension.js';
+import { Extension } from 'resource:///org/gnome/shell/extensions/extension.js';
 import * as Main from 'resource:///org/gnome/shell/ui/main.js';
-import MessageTray from 'resource:///org/gnome/shell/ui/messageTray.js';
+import { MessageTray } from 'resource:///org/gnome/shell/ui/messageTray.js';
 import * as Utils from './utils.js';
 
 const BannerBin = Main.messageTray._bannerBin;
-import {NOTIFICATION_TIMEOUT, HIDE_TIMEOUT, LONGER_HIDE_TIMEOUT, IDLE_TIME, State, Urgency } from 'resource:///org/gnome/shell/ui/messageTray.js';
+import { State, Urgency } from 'resource:///org/gnome/shell/ui/messageTray.js';
+
+const NOTIFICATION_TIMEOUT = 4000;
+const HIDE_TIMEOUT = 200;
+const LONGER_HIDE_TIMEOUT = 600;
+const IDLE_TIME = 1000;
 
 let ANIMATION_TIME = 200;
 let ANIMATION_DIRECTION = 2;
@@ -47,7 +52,11 @@ function patcher(obj, live, method, original, patch) {
     eval(`${live}.${method} = ${newBody}`);
 }
 
-const getMessageTraySize = () => ({ width, height } = Main.layoutManager.getWorkAreaForMonitor(global.display.get_primary_monitor()));
+const getMessageTraySize = () => {
+    var width, height;
+    var { width, height } = Main.layoutManager.getWorkAreaForMonitor(global.display.get_primary_monitor());
+    return {width, height};
+}
 
 const originalShow = MessageTray.prototype._showNotification;
 const originalHide = MessageTray.prototype._hideNotification;
@@ -160,7 +169,8 @@ const always_minimize_patch = {
 };
 
 export default class NotificationExtension extends Extension {
-    constructor() {
+    constructor(metadata) {
+        super(metadata);
         this._previous_y_align = BannerBin.get_y_align();
         this._previous_x_align = BannerBin.get_x_align();
     }
diff --git a/metadata.json b/metadata.json
index 7df3e57..65be373 100644
--- a/metadata.json
+++ b/metadata.json
@@ -5,7 +5,7 @@
   "description": "Configure notification banner position and animation to your liking",
   "uuid": "notification-banner-reloaded@marcinjakubowski.github.com",
   "shell-version": [
-    "45",
+    "45"
   ],
   "url": "https://github.com/marcinjakubowski/notification-position-reloaded",
   "settings-schema": "org.gnome.shell.extensions.notification-banner-reloaded"
diff --git a/prefs.js b/prefs.js
index d991a45..3ae9a15 100644
--- a/prefs.js
+++ b/prefs.js
@@ -46,7 +46,23 @@ function init() {
 }
 
 export default class NotificationExtensionPreferences extends ExtensionPreferences {
-    constructor() {
+    constructor(metadata) {
+        super(metadata);
+    }
+
+    getPreferencesWidget() {
+        let frame = new Gtk.Box();
+        let widget = new Preferences(this.getSettings());
+        addBox(frame, widget.main);
+        if (frame.show_all)
+            frame.show_all();
+        return frame;
+    }
+}
+
+class Preferences{
+    constructor(settings) {
+        this.settings = settings
         this.main = new Gtk.Grid({
             margin_top: 10,
             margin_bottom: 10,
@@ -164,7 +180,6 @@ export default class NotificationExtensionPreferences extends ExtensionPreferenc
         addRow(animationTimeLabel,        this.animationTime);
         addRow(alwaysMinimizeLabel,       this.alwaysMinimize);
 
-        const settings = this.getSettings();
         settings.bind(Utils.PrefFields.ANCHOR_HORIZONTAL,   this.anchorHorizontal,      'active', Gio.SettingsBindFlags.DEFAULT);
         settings.bind(Utils.PrefFields.ANCHOR_VERTICAL,     this.anchorVertical,        'active', Gio.SettingsBindFlags.DEFAULT);
         settings.bind(Utils.PrefFields.PADDING_HORIZONTAL,  this.paddingHorizontal,     'value',  Gio.SettingsBindFlags.DEFAULT);
@@ -186,13 +201,3 @@ export default class NotificationExtensionPreferences extends ExtensionPreferenc
         return liststore;
     }
 };
-
-function buildPrefsWidget() {
-    let frame = new Gtk.Box();
-    let widget = new Preferences();
-    addBox(frame, widget.main);
-    if (frame.show_all)
-	    frame.show_all();
-    return frame;
-}
-
diff --git a/utils.js b/utils.js
index f96c1a9..3771286 100644
--- a/utils.js
+++ b/utils.js
@@ -1,4 +1,4 @@
-var PrefFields = {
+export const PrefFields = {
     ANCHOR_VERTICAL        : 'anchor-vertical',
     ANCHOR_HORIZONTAL      : 'anchor-horizontal',
     PADDING_VERTICAL       : 'padding-vertical',