Send a Slack webhook when a Chrome page changes

Send a Slack, Discord, or ntfy message from Tab Automation while Chrome is open. Pair Wait Until or If / Else with Send Alert. Not a monitor after you quit.

Tab Automation

Tab Automation can send a Slack, Discord, or ntfy message when Send Alert runs. Put that step after Wait Until if the page may change later, or in If / Else if you only need a check at that moment.

Chrome must stay open. This is not a monitor that keeps checking after you quit Chrome. Chrome sends the message from this computer. Nothing relays through Tab Automation servers.

When a webhook should fire

A webhook fires only when the runner reaches a moment that has Webhook on and a destination selected. The check and the message are separate steps.

  • Use Wait / Delay Until when the loaded page may change later and the automation should poll until it does.
  • Use If / Else when the next steps depend on the page right now, at that step.
  • Use Send Alert only where a message should go out.

If / Else does not keep watching. Wait Until polls every 250 milliseconds until the condition succeeds or the timeout ends. A timeout records a warning and the graph continues, so Send Alert after Until also runs after a timeout unless you turn on Pause when this wait succeeds.

The auto refresh vs page monitor guide is the longer split between a timer, a one-time check, and Until.

Add a destination in Settings

  1. Open the Tab Automation side panel.
  2. Open Settings from the masthead gear.
  3. Under Webhooks, click Add a destination.
  4. Give it a name and paste an HTTPS URL. HTTP is allowed only on this computer (localhost, 127.0.0.1, or ::1).
  5. Save. Destinations are a shared library on this computer.

Create the URL in the service you already use:

Tab Automation does not create a Slack app, sign you in, or send email or SMS. There is no Microsoft Teams adapter. Any other HTTPS URL is fine if that host accepts a JSON body from Chrome.

Turn Webhook on at the moment

  1. Add Send Alert where the run should notify — in If Then or Else, or after Wait Until.
  2. Turn Webhook on. Add Step leaves desktop notification and sound on; you can leave those on or turn one off.
  3. Pick one or more destinations. Optionally override the message on this step.
  4. Click Test on Webhook only. That pill sends to the destinations on this step and does not use Chrome’s OS notification permission.

Repeat Each cycle and When it stops can also send a webhook. Both stay off until you enable them. Each moment picks its own destinations.

Use {{name}} in the message to insert a Values name saved earlier in the graph. Settings Test interpolates against an empty map and warns when the template contains {{name}}.

Nothing posts until a destination is selected and Webhook is on for that moment.

What the destination receives

Slack, Discord, and ntfy show the resolved message, the current page URL, and the event (notify, cycle, stop, or test). Chrome sends that from this computer. Delivery waits up to five seconds. A failed or timed-out send does not stop the automation.

Any other HTTPS URL receives the same facts as a JSON body. A self-hosted ntfy server is treated that way too.

Open Activity for a redacted delivery line. The URL and secrets are not written in full.

Desktop notification vs webhook

Desktop Test asks the operating system to show a Chrome banner. If that test is silent, follow Chrome notifications not working. Allow Google Chrome in the OS. Website notification settings for a page are a different switch.

Webhook Test is a separate check. It does not use that OS permission.

Limits to know before you start

  • Chrome must stay open. Alarms do not fire after you quit Chrome. Running automations are rescheduled when Chrome starts again. There is no cloud check while the browser is closed.
  • Wait Until only polls during that step. It is not a background watcher after the run ends.
  • There is no email or SMS. Destinations are HTTPS webhooks you saved in Settings.
  • There is no clock-time start. Repeat waits between cycles; it does not start at 9:00.
  • Some tabs cannot be automated. Chrome UI pages, extension pages, and the Chrome Web Store are excluded.
  • Browser support is limited. Desktop Chrome, Edge, Brave, and Opera can install the Chrome Web Store listing. Firefox, Safari, and mobile are not supported.

Automations and destinations stay in chrome.storage.local on this computer. Read the privacy policy for permissions and data handling.

Tab Automation is not on the Chrome Web Store yet. See how an automation is built, then come back when a listing exists.

See how it works
How-to · How to auto click a button in ChromeChrome has no built-in repeating click. Pick one button in Tab Automation, add Click Element plus Repeat, or try a short-lived console script.How-to · Updated How to walk through links in ChromeCollect matching links from one Chrome page, open each URL in the same assigned tab, and run a repeatable set of steps on every page.How-to · Updated Chrome notifications not working? Fix silent alertsTroubleshoot silent Tab Automation alerts on macOS, Windows, or Linux: test output, allow Chrome in the OS, check Focus, then verify the run.