1. Rejected this one because Util.toggleCSS() may work but since you are doing that to Main.panel it needs to get refactored. You should (almost) never modify the class name string that is owned by the St.Widget. Instead of using the entire style string use these methods: object.has_style_class_name(className); object.add_style_class_name(className); Read more about these methods here: https://gjs-docs.gnome.org/st10~1.0_api/st.widget#method-has_style_class_name 2. This one is just a recommendation: I think you don't need to use `force` after using St.Widget.add_style_class_name() but If you still want to use `force` in Util.toggleCSS(), it's a good practice to make `force` as boolean. default shouldn't be null. It should be true or false. 3. Please remove custom getSettings function. Use ExtensionUtils.getSettings() instead: https://gitlab.gnome.org/GNOME/gnome-shell/-/blob/5dfc3c1ef85db9267f37efffe958c6ae4b493a37/js/misc/extensionUtils.js#L176-212 If you need any help with your extension you can ask us on: GNOME Matrix channel: https://matrix.to/#/#extensions:gnome.org IRC Bridge: irc://irc.gimpnet.org/shell-extensions