Examine source code of BF4 True Player Count

{
  "name": "Battlefield 4 True Player Count",
  "description": "Shows the true player count for Battlefield 4 servers listed on Battlelog",
  "version": "0.0.0.3",
  "browser_action": {
    "default_icon": "Img/ExtLogo-16x16.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.battlelog.battlefield.com/bf4/servers/*"
      ],
      "js": [
        "getPlayerCount.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "http://*.battlelog.battlefield.com/bf4/servers/*",
    "https://keeper.battlelog.com/snapshot/*"
  ],
  "icons": {
    "16": "Img/ExtLogo-16x16.png",
    "32": "Img/ExtLogo-32x32.png",
    "48": "Img/ExtLogo-48x48.png",
    "128": "Img/ExtLogo-128x128.png"
  },
  "manifest_version": 2
}