Privacy Policy for Event Watcher

Last Updated: March 2026

Overview

Event Watcher is a browser developer tools extension that helps developers debug analytics implementations. This privacy policy explains how the extension handles data.

Data Collection

Analytics We Collect

Event Watcher collects anonymous usage analytics to help improve the extension. We use Amplitude (EU data residency) to track:

Extension open/close events
Feature usage (which filters are used, etc.)
App version and platform

What we DO NOT collect:

No personal information (name, email, etc.)
No browsing history or URLs
No website content or tracking data you're debugging
No IP addresses (Amplitude EU is configured without IP tracking)

How It Works

A random device ID is generated locally (not linked to your identity)
No cookies are used
No user accounts or login required
Data is sent to Amplitude's EU servers

Opt-Out

You can disable analytics in the extension settings. When disabled, no data is sent to Amplitude.

What the Extension Does Locally

Monitors network requests on the current tab to detect analytics tracking calls
Parses tracking data locally in your browser for display in the DevTools panel
Stores your filter preferences and settings locally using Chrome's storage API
GTM Hub: Can block, swap, inject, or preview Google Tag Manager containers on websites you are debugging. These modifications apply only to your local browser session and are not persisted on the website
Consent Monitoring:Detects Consent Management Platforms (CMPs) on the page and reads their consent state to check whether tracking events comply with the user's consent choices. No consent data is collected or transmitted
Custom Endpoints: Allows you to define custom domain-to-tool mappings so the extension can recognize 1st-party proxies and CNAME-cloaked tracking endpoints. These mappings are stored locally in your browser
Cookie Monitoring: Reads cookies set by detected tracking platforms on the current page for display in the DevTools panel. Cookie data is processed locally and never transmitted

Permissions Explained

The extension requires the following permissions:

Permission	Purpose
`webNavigation`	Detect page navigations to group events by page and clear events on new page loads
`webRequest`	Observe network request URLs to detect tracking platforms (read-only, no request content is captured)
`storage`	Save your preferences and settings locally
`sidePanel`	Provide a side panel view for a quick tracking summary from the browser toolbar
`cookies`	Read cookies set by detected tracking platforms for local display in the DevTools panel
`declarativeNetRequest`	Used by GTM Hub to block, swap, or inject GTM containers on the current page (local session only)
`<all_urls>`	Monitor network requests on any website you're debugging

Data Storage

Session Data: Captured events are stored in memory and cleared when you close the DevTools panel or navigate to a new page
Preferences:Filter settings, view mode defaults, and analytics opt-out preference are stored locally using Chrome's storage.local API
GTM Hub Rules:Container block, swap, inject, and preview rules are stored locally per domain using Chrome's storage API
Custom Endpoints: Custom domain-to-tool mappings are stored locally in your browser and do not sync across devices
Analytics: Anonymous usage data is sent to Amplitude (EU) unless you opt out

Contact

For questions about this privacy policy or the extension:

Author: Rune Andersen

Changes to This Policy

Any updates to this privacy policy will be reflected in the Chrome Web Store listing.