Examine source code of Tab Cemetery Timer

{
  "manifest_version" : 2 ,
  "name" : "Tab Cemetery",
  "version" : "1.4.1",
  "description" : "A focused Firefox tab timer with a fast popup and recoverable expiry screen.",
  "permissions" : [
    "tabs" ,
    "storage" ,
    "alarms" 
  ],
  "background" : {
    "scripts" : [
      "shared.js" ,
      "background.js" 
    ]
  },
  "browser_action" : {
    "default_title" : "Open Tab Cemetery",
    "default_popup" : "popup.html",
    "default_icon" : {
      "16" : "assets/icon-16.png",
      "32" : "assets/icon-32.png",
      "48" : "assets/icon-48.png",
      "96" : "assets/icon-96.png"
    }
  },
  "icons" : {
    "16" : "assets/icon-16.png",
    "32" : "assets/icon-32.png",
    "48" : "assets/icon-48.png",
    "96" : "assets/icon-96.png",
    "128" : "assets/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "tab-cemetery@local-first.example",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}