Once the task is complete, enter the Task ID: new-cache-used
Now you're ready to activate the new Service Worker. As we saw earlier, the Service Worker won't activate until pages using the current version go away.
Either close this tab, navigate it to a page out of the Service Workers scope, or hold SHIFT and reload the page.
Once you've done this, when you navigate back to the Wittr application it should be showing the new theme. To confirm this, enter the task ID into the test page and press enter.