Examine source code of HN Dark Mode

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    "256": "images/HackerNewsColor-256.png",
    "512": "images/HackerNewsColor-512.png"
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    "scripts": [
      "background.js"
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  "content_scripts": [
    {
      "js": [
        "content.js"
      ],
      "css": [
        "style.css"
      ],
      "matches": [
        "*://news.ycombinator.com/*"
      ]
    }
  ],
  "browser_action": {
    "default_popup": "popup.html"
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  "permissions": [
    "storage"
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}