Users are so annoying! There they go, leaving the page before we can save the data to the API. Back in the old days, we would attach a `window.unload` handler and try to send an AJAX request, but this was slow and unreliable.

Enter the Beacon API to give us a better way.

The Beacon provides a reliable way to send a small amount of data *after* the page has been unloaded. It's not bound to the lifetime of the page and it doesn't slow down the user.

Read more at https://requestmetrics.com/making-of/using-the-beacon-api