Examine source code of Scratch Color Changer

{
  "name": "Scratch Color Changer",
  "description": "Change the color of the Scratch website at will",
  "version": "0.3",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "https://*.scratch.mit.edu/*"
  ],
  "browser_action": {
    "default_popup": "popup.html"
  },
  "icons": {
    "32": "icon.svg",
    "64": "icon.svg"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a1c9a937-23c0-46f5-afce-87da576251ce}"
    }
  }
}