Examine source code of StealthMail Link detector

{
  "author": "StealthMail",
  "applications": {
    "gecko": {
      "id": "StealthMailLinker@stealthmail.com"
    }
  },
  "background": {
    "page": "background.html",
    "persistent": true
  },
  "content_scripts": [
    {
      "run_at": "document_start",
      "matches": [
        "https://*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "description": "An extension that detects StealthMail secure links on the web email clients and opens them in StealthMail Client application.",
  "icons": {
    "16": "/images/sm_icon_16.png",
    "32": "/images/sm_icon_32.png",
    "48": "/images/sm_icon_48.png",
    "64": "/images/sm_icon_64.png",
    "128": "/images/sm_icon_128.png"
  },
  "manifest_version": 2,
  "name": "StealthMail Link detector",
  "permissions": [
    "storage",
    "webNavigation",
    "https://*/*",
    "tabs",
    "management"
  ],
  "version": "1.4"
}