Examine source code of GSLab Screen Sharing App

{
  "description": "The new GSLab extension allows you to capture your screen and share the Screen",
  "manifest_version": 2,
  "name": "GSLab Screen Sharing App",
  "version": "1.7resigned1",
  "icons": {
    "48": "icons/k48.png"
  },
  "applications": {
    "gecko": {
      "id": "skreenme@gslab.com",
      "strict_min_version": "50.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "js": [
        "page.js"
      ],
      "matches": [
        "*://skreen.me/*",
        "*://testskreenme.gslab.com/*",
        "*://go.skreen.me/*"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_action": {
    "default_icon": "icons/k48.png"
  },
  "permissions": [
    "activeTab",
    "notifications",
    "nativeMessaging"
  ]
}