Run Javascript

Tracking since Apr 18, 2026.

Changelog

• May 20, 2026
  description

  🐘 Transform Any Website Into Your Personal Playground with Custom JavaScript
  
  The Ultimate Chrome Extension for Web Developers, Power Users & Automation Enthusiasts
  
  Take complete control of your browsing experience! This powerful extension lets you run custom JavaScript on
  any website automatically, turning every page into your personal development sandbox.
  
  ## ✨ What Makes This Extension Amazing?
  
  🎯 Instant Website Customization
  ✅ Run custom JavaScript on ANY website automatically
  ✅ Real-time code editor with syntax highlighting
  ✅ Domain-specific scripts that persist forever
  ✅ One-click enable/disable toggle
  
  💻 Professional Developer Experience
  ✅ Built-in Ace Editor with intelligent code completion
  ✅ Multiple jQuery versions (1.12.4, 2.2.4, 3.3.1) or go library-free
  ✅ Persistent storage across browser sessions
  ✅ Advanced error handling and debugging tools
  
  🔒 Enterprise-Grade Security
  ✅ Manifest V3 compliant (latest Chrome standards)
  ✅ Sandboxed execution environment
  ✅ Modern service worker architecture
  ✅ Smart duplicate execution prevention
  
  ## 🌟 Perfect For:
  
  🧑💻 Web Developers - Test ideas, prototype features, debug issues instantly
  🔧 Power Users - Customize websites to match your exact workflow
  📈 Digital Marketers - A/B test changes, extract analytics data
  🎓 Students & Educators - Learn JavaScript in real-world environments
  🤖 Automation Enthusiasts - Automate repetitive web tasks effortlessly
  
  ## 🎮 Real-World Use Cases:
  
  • Remove annoying ads and popups with surgical precision
  • Auto-fill forms with your personal data
  • Change website themes to dark mode or custom colors
  • Extract data from any page for analysis
  • Add missing features that websites should have
  • Create productivity dashboards on any site
  • Automate repetitive clicks and form submissions
  • Test responsive designs with custom CSS
  
  ## 🚀 Why Choose This Over Others?
  
  | Feature | This Extension | Others |
  |---------|---------------|---------|
  | Ease of Use | ✅ One-click setup | ❌ Complex config |
  | Security | ✅ Manifest V3 + Sandboxing | ❌ Outdated security |
  | Performance | ✅ Modern architecture | ❌ Legacy code |
  | Developer Experience | ✅ Syntax highlighting + jQuery | ❌ Plain text editors |
  | Reliability | ✅ Smart execution prevention | ❌ Script conflicts |
  
  ## ⚡ Get Started in 60 Seconds:
  
  1. Install the extension
  2. Visit any website you want to customize
  3. Click the extension icon in your toolbar
  4. Write JavaScript or choose from templates
  5. Hit "Save & Run" and watch the magic happen! ✨
  
  No coding experience? No problem! Start with simple examples like changing colors or hiding elements, then
  gradually build more complex automations.
  
  ## 🎯 Immediate Benefits:
  
  • Save hours daily by automating repetitive tasks
  • Fix annoying UI issues that developers ignore
  • Learn JavaScript in a practical, fun environment
  • Boost productivity with personalized web experiences
  • Join a community of creative web customizers
  
  Transform your browsing experience today! Whether you're automating tasks, learning to code, or just making
  the web work better for you, this extension is your gateway to unlimited possibilities.
  
  🌟 Ready to take control of the web? Install now and start customizing!

  ⚡ Run custom JavaScript on any website — automatically, every time you visit.
  
  Save your scripts per domain. They execute on page load, every single time. No setup, no config files, no extra tools. Just your code running where you want it.
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  🔧 HOW IT WORKS
  
  1. Visit any website
  2. Click the Run JavaScript icon
  3. Write or paste your custom JavaScript code
  4. Save — your script auto-runs on every future visit to that domain
  
  Toggle scripts on/off per site with one click. Scripts persist across browser restarts.
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  🎯 WHAT YOU CAN DO
  
  ✅ Remove ads, popups, banners, cookie notices, and distracting elements
  ✅ Inject custom CSS — dark mode, custom themes, font changes, layout fixes
  ✅ Auto-fill forms, pre-select dropdowns, auto-click buttons
  ✅ Auto-run scripts on page load without manual intervention
  ✅ Extract data, scrape content, highlight information on any page
  ✅ Add features websites are missing — keyboard shortcuts, UI tweaks
  ✅ Automate repetitive tasks — clicks, form submissions, navigation
  ✅ Inject custom HTML elements, dashboards, or productivity widgets
  ✅ Test and prototype frontend code changes on live websites
  ✅ Debug and inspect page behavior with custom console scripts
  ✅ Modify DOM elements, rewrite page content, restructure layouts
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  💻 BUILT FOR DEVELOPERS
  
  ✅ Ace code editor with full syntax highlighting and auto-indent
  ✅ jQuery library included (1.12.4, 2.2.4, 3.3.1) — or use vanilla JavaScript
  ✅ Execute button for instant testing before saving
  ✅ Scripts stored per hostname using Chrome storage API
  ✅ One-click enable/disable toggle per domain
  ✅ Works on all http and https pages
  ✅ Manifest V3 — secure, fast, modern Chrome extension architecture
  ✅ Service worker background script — no performance overhead
  ✅ Sandboxed execution with duplicate run prevention
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  👤 WHO USES THIS
  
  → Web developers testing and debugging on production sites
  → Frontend engineers prototyping UI changes live
  → QA testers injecting test scripts and automation
  → Digital marketers running A/B tests and analytics scripts
  → Power users customizing websites to fit their workflow
  → Students learning JavaScript with real-world web pages
  → Automation enthusiasts replacing repetitive manual tasks
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  📝 EXAMPLE SCRIPTS
  
  Remove cookie banners:
  document.querySelector('[class*="cookie"]')?.remove()
  
  Force dark mode on any site:
  document.body.style.cssText = 'background:#1a1a1a!important;color:#eee!important'
  
  Auto-expand collapsed content:
  document.querySelectorAll('[aria-expanded="false"]').forEach(el => el.click())
  
  Hide sidebar navigation:
  document.querySelector('aside')?.style.display = 'none'
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  🔒 PRIVACY & SECURITY
  
  → No data collection, no tracking, no analytics
  → No account required — works immediately after install
  → All scripts stored locally in your browser
  → Open source and transparent
  → Manifest V3 security standards
  → No external network requests
  
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  
  Lightweight. Fast. Private. Just your JavaScript, running where you want it.
  
  Install now → click the icon → paste your code → done.

Permissions & access

Permissions

storageactiveTabscriptingalarmstabs

Host access

http://*/*, https://*/*

Screenshots

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