Examine source code of Custom Scrollbars

{
  "manifest_version" : 2 ,
  "name" : "__MSG_extensionName__" ,
  "version" : "4.5.1",
  "description" : "__MSG_extensionDescription__" ,
  "author": "Wesley Branton",
  "default_locale" : "en" ,
  "developer": {
    "name" : "Wesley Branton",
    "url": "http://addons.wesleybranton.com"
  },
  "icons" : {
    "32" : "icons/icon-32.png",
    "48" : "icons/icon-48.png",
    "64" : "icons/icon-64.png",
    "96" : "icons/icon-96.png",
    "128" : "icons/icon-128.png"
  },
  "browser_action" : {
    "default_icon" : {
      "32" : "icons/icon-32.png",
      "48" : "icons/icon-48.png",
      "64" : "icons/icon-64.png",
      "96" : "icons/icon-96.png",
      "128" : "icons/icon-128.png"
    },
    "default_title" : "__MSG_extensionName__" ,
    "default_popup" : "popup/popup.html"
  },
  "options_ui" : {
    "page": "options/scrollbars.html" ,
    "browser_style": false,
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "customscrollbars@computerwhiz",
      "strict_min_version": "64.0"
    }
  },
  "background" : {
    "scripts" : [
      "defaults.js" ,
      "generateCSS.js" ,
      "crossbrowser.js" ,
      "background.js" 
    ]
  },
  "content_scripts" : [
    {
      "matches" : [
        "<all_urls>" 
      ],
      "js" : [
        "content.js" 
      ],
      "all_frames" : true ,
      "run_at" : "document_start" 
    },
    {
      "matches" : [
        "*://addons.wesleybranton.com/addon/custom-scrollbars/*" ,
        "*://customscrollbars.com/*" 
      ],
      "js" : [
        "crossbrowser.js" ,
        "webservice/unsubscribeFromNotifications.js" ,
        "webservice/openOptions.js" 
      ],
      "all_frames" : false ,
      "run_at" : "document_end" 
    }
  ],
  "permissions" : [
    "storage" ,
    "<all_urls>" 
  ],
  "optional_permissions" : [
    "downloads" 
  ]
}