Examine source code of vMonitor

{
  "manifest_version": 2,
  "icons": {
    "16": "img/vIcon-small.png",
    "48": "img/vIcon-medium.png",
    "128": "img/vIcon-large.png"
  },
  "name": "vMonitor",
  "short_name": "The Valsto vMonitor",
  "description": "Valsto Browser Extension",
  "version": "1.1.11resigned1",
  "browser_action": {
    "default_title": "My vMonitor",
    "default_icon": {
      "16": "img/vIcon-small.png"
    }
  },
  "background": {
    "scripts": [
      "vMonitor.js"
    ]
  },
  "permissions": [
    "cookies",
    "<all_urls>",
    "history",
    "storage"
  ],
  "web_accessible_resources": [
    "vMonitorPublic.html"
  ],
  "applications": {
    "gecko": {
      "id": "vmonitor@valsto.com",
      "strict_min_version": "42.0"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.valsto.com/*"
      ],
      "js": [
        "vMonitor.js"
      ]
    }
  ]
}