Examine source code of Date and Time

{
  "manifest_version": 2,
  "name": "Date and Time",
  "version": "3.1resigned1",
  "description": "A Popup Time and Date on Toolbar",
  "icons": {
    "32": "icons/icon1.jpg",
    "48": "icons/icon2.jpg",
    "96": "icons/icon2.jpg"
  },
  "author": "Azharul Islam",
  "applications": {
    "gecko": {
      "id": "azharul.sylhet@gmail.com",
      "strict_min_version": "42.0",
      "strict_max_version": "50.*"
    }
  },
  "homepage_url": "https://github.com/azharul96/timer-addons",
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "celender.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/icon1.jpg"
    },
    "default_popup": "index.html"
  },
  "permissions": [
    "webRequest"
  ]
}