Examine source code of Yet Another Smooth Scrolling WE

{
  "manifest_version" : 2 ,
  "name" : "Yet Another Smooth Scrolling WE",
  "version" : "2.0.14",
  "description" : "__MSG_extensionDescription__" ,
  "author": "kataho",
  "default_locale" : "en" ,
  "permissions" : [
    "storage" 
  ],
  "icons" : {
    "32" : "img/wheel.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "yetanothersmoothscrollingwe@kataho",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "content_scripts" : [
    {
      "run_at" : "document_start" ,
      "matches" : [
        "<all_urls>" 
      ],
      "js" : [
        "util.js" ,
        "scroller.js" ,
        "content.js" 
      ],
      "match_about_blank" : true ,
      "all_frames" : true 
    }
  ],
  "background" : {
    "scripts" : [
      "util.js" ,
      "background.js" 
    ]
  },
  "options_ui" : {
    "page": "options.html" ,
    "open_in_tab": true
  },
  "browser_action" : {
    "browser_style": true,
    "default_icon" : {
      "16" : "img/wheel16.png",
      "32" : "img/wheel.png"
    },
    "default_title" : "Smooth Scroll",
    "default_popup" : "popup.html"
  },
  "web_accessible_resources" : [
    "img/edgebgbot.png",
    "img/edgebgtop.png"
  ]
}