1. No need to include the assets folder if the compiled file has everything. The compiled resource file would be enough. 2. Please don't store any instance of objects in a property of the default class you are exporting in `prefs.js`. You also have some global variables (line 13-15 `prefs.js`). That won't allow the garbage collector to do its job after window close: [EGO Review Guidelines: Destroy](https://gjs.guide/extensions/review-guidelines/review-guidelines.html#destroy-all-objects) If you don't want to move them to another class or make it local to `fillPreferencesWindow()` function, you can clean up on: ```js window.connect('close-request', () => { // clean up here }); ``` 3. Please don't call functions in global scope: - line 289-300 `serial.js` - line 24-29 `utils/state.js`