Open your Chrome browser and go to the site where Speed Kit is installed on. Click on your Speed Kit bookmarklet and wait until the popup appears. The popup will show some information about the current navigation and also lets you change the Speed Kit group. To switch to the Speed Kit group, type “A” into the textfield, hit “OK” and reload to install the service worker. To leave the Speed Kit group, type “B” into the text field, hit “OK” and reload to uninstall the service worker. The bookmarklet works accordingly in other browsers.