Examine source code of Calcatom

{
  "manifest_version" : 2 ,
  "name" : "__MSG_extensionName__" ,
  "description" : "__MSG_extensionDescription__" ,
  "version" : "1.0.4",
  "icons" : {
    "16" : "icon/16.png",
    "256" : "icon/256.png"
  },
  "default_locale" : "en_US" ,
  "permissions" : [
    "storage" 
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "dev@nearmelab.digital",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "sidebar_action": {
    "default_icon" : "icon/logo.png",
    "default_panel": "popup.html"
  },
  "browser_action" : {
    "default_title" : "Calcatom",
    "default_popup" : "popup.html"
  }
}