Examine source code of Explore Fibonacci

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  "name": "Explore Fibonacci",
  "version": "1.2.1",
  "description": "Explore Fibonacci numbers and the golden ratio visually",
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  "icons": {
    "16": "media/n16.png",
    "32": "media/n32.png",
    "48": "media/n48.png",
    "96": "media/n96.png",
    "128": "media/n128.png"
  },
  "browser_action": {
    "default_popup": "display/view.html",
    "default_icon": {
      "16": "media/n16.png",
      "32": "media/n32.png",
      "48": "media/n48.png",
      "96": "media/n96.png",
      "128": "media/n128.png"
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  },
  "background": {
    "scripts": [
      "runtime/engine.js"
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  "permissions": []
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