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Preview of JavaScript Playground ⚡ Online JS Compiler

JavaScript Playground ⚡ Online JS Compiler by onyxwizard

**Write and run JavaScript code instantly.** Skip the setup and open a distraction-free playground with a single click. Test functions, debug concepts, or learn new features right in a dedicated popup. just pure, instant JS code execution.

Available on Firefox for Android™Available on Firefox for Android™
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About this extension
A lightweight, cyber‑themed JavaScript playground that lives in your browser. Click the toolbar icon → a new tab opens with a side‑by‑side editor and output panel.

✅ Features:
• Real‑time evaluation – auto‑runs as you type (toggle on/off)
• Manual run via button or Ctrl+Enter
• Full JavaScript syntax highlighting (CodeMirror with Darcula theme)
• Console.log capture – shows output in the right panel
• Error display with clear visual feedback
• Persistent storage – your code is saved automatically
• Clean, responsive dark cyber design

No tracking, no data collection, no external servers – everything runs locally in your browser.
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Permissions and data

Required permissions:

  • Access browser tabs

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
  • Support site
Version
1.1
Size
95.05 KB
Last updated
8 days ago (Feb 13, 2026)
Related Categories
  • Web Development
License
MIT License
Version History
  • See all versions
Tags
  • user scripts
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