Examine source code of Edge Scroller

{
  "name": "Edge Scroller",
  "description": "Scrolling by carry mouse to edge.",
  "manifest_version": 2,
  "version": "1.1resigned1",
  "icons": {
    "64": "icons/select64.png"
  },
  "browser_action": {
    "default_icon": {
      "32": "icons/select32_off.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "subfunc.js",
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "permissions": [
    "<all_urls>",
    "activeTab",
    "tabs",
    "webNavigation",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f88fd58e-c888-4557-8d5f-88985ecc86e8}"
    }
  }
}