Examine source code of Scroll Counter

{
  "manifest_version": 2,
  "name": "Scroll Counter",
  "version": "1.0",
  "description": "Displays a small clock counting daily scrolls.",
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{97405caf-f8d2-429b-99f9-7678058d1346}"
    }
  }
}