Examine source code of Snake

{
  "manifest_version": 2,
  "name": "Snake",
  "description": "Play Snake right on your screen.",
  "version": "2.7resigned1",
  "icons": {
    "32": "icons/icon_32.png",
    "48": "icons/icon_48.png",
    "64": "icons/icon_64.png",
    "128": "icons/icon_128.png"
  },
  "browser_action": {
    "default_icon": "icons/icon_32.png",
    "default_title": "Snake"
  },
  "background": {
    "scripts": [
      "js/bg.js"
    ]
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{66a769a6-87b3-4702-bf86-58bf53cdade4}"
    }
  }
}