Element Alert

About

Monitor specific DOM elements on web pages and get instant notifications when they
  change. Perfect for tracking prices, stock availability, status updates, and any
  dynamic content on websites.

  🎯 KEY FEATURES

  • Multiple Monitoring Rules - Set up unlimited monitoring rules for different pages
   and elements
  • Visual Element Selection - Simply click on any element to start monitoring it
  • 10 Notification Sounds - Choose from 10 different alert sounds to match your
  preference
  • URL Pattern Matching - Use wildcards to monitor elements across multiple pages
  • Real-time Detection - Instant notifications using MutationObserver technology
  • Smart Notifications - Desktop alerts with page title and element content
  • Notification History - Keep track of all detected changes
  • Customizable Settings - Control check intervals, sound volume, and more

  🚀 USE CASES

  • Price Monitoring - Track product prices on e-commerce sites like Amazon, eBay
  • Stock Availability - Get notified when out-of-stock items become available
  • Order Tracking - Monitor shipping status and delivery updates
  • Social Media - Watch follower counts, likes, or engagement metrics
  • News Updates - Stay informed when articles or headlines change
  • Content Changes - Monitor any text, number, or status on any website

  📖 HOW TO USE

  1. Click the extension icon in your toolbar
  2. Click "要素を選択" (Select Element) button
  3. Hover over and click the element you want to monitor
  4. Give your rule a name (e.g., "Price Monitor")
  5. Save the rule
  6. Receive notifications whenever the element changes!

  🔧 TECHNICAL DETAILS

  • Uses MutationObserver API for instant change detection
  • Periodic checking as fallback for maximum reliability
  • Manifest V3 compliant
  • Minimal performance impact
  • Works on all websites
  • No data collection or tracking

  💡 PERFECT FOR

  Shoppers tracking deals, developers monitoring web services, researchers tracking
  data, stock traders watching prices, or anyone who needs to stay updated on web
  content changes.

  🌐 OPEN SOURCE

  Element Alert is open source! View the code, contribute, or report issues on
  GitHub:
  https://github.com/tomohiro-owada/element-alert

  ⭐ Support the project by leaving a review!