> For the complete documentation index, see [llms.txt](https://www.fullstackfirebase.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.fullstackfirebase.com/cloud-messaging/walkthrough.md).

# Walkthrough

## Open the app

Open the app at <https://fine-ping.glitch.me/>.

## Open DevTools

Right-click `inspect element` and select the `Debugger` tab. Then click `command + P` to search for and open two files:

* `client.js`,
* and `firebase-messaging-sw.js`.

You'll likely need to open the `Application` tab in DevTools and navigate to the `Service Workers` side tab. Then click the link for `firebase-messaging-sw.js` to inspect it in the `Sources` tab.

![client.js](https://goo.gl/3EmcES)

![firebase-messaging-sw.js](https://goo.gl/xoGxvx)

## Video

{% embed url="<https://youtu.be/QaTNDARGH0E>" %}