Examine source code of Browsing Stats

{
  "manifest_version": 2,
  "name": "Browsing Stats",
  "version": "1.0.0",
  "permissions": [
    "activeTab",
    "tabs",
    "unlimitedStorage",
    "storage"
  ],
  "background": {
    "scripts": [
      "src/engine/Background.js"
    ]
  },
  "icons": {
    "192": "icons/mainIcon.png",
    "384": "icons/mainIcon@2x.png",
    "800": "icons/mainIcon@4x.png"
  },
  "description": "Monitors and display stats about visiting websites",
  "browser_action": {
    "default_title": "Browsing Stats",
    "default_popup": "src/popup/Popup.html",
    "default_icon": "icons/mainIcon@4x.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{659f230e-af51-473e-beba-e00b65d653b5}"
    }
  }
}