Fix Datasense not receiving events

Check these in order:

1. You're on localhost. The script ignores localhost, 127.0.0.1 and file: pages. Add data-allow-localhost="true" to test locally.
2. An ad blocker is on. Try a private window without extensions, then set up the proxy.
3. The domain doesn't match. Events are only accepted from the domain you added and its subdomains.
4. You opted out on this browser. Run localStorage.removeItem("datasense_ignore").
5. The script isn't on the page. View the page source and look for data-website-id. In the network tab, script.js should load and /api/e should answer 202.
6. A Content Security Policy blocks it. See fix CSP.
7. This month's events are used up. Collection continues, but reports lock until the 1st or an upgrade. Billing shows usage.