Examine source code of Share for Helium

{
  "name": "Share for Helium",
  "version": "1.2.3resigned1",
  "manifest_version": 2,
  "minimum_chrome_version": "41.0.2272.76",
  "description": "Share your web page with Helium on OS X.",
  "icons": {
    "16": "img/icon-16.png",
    "32": "img/icon-32.png",
    "48": "img/icon-48.png",
    "64": "img/icon-64.png",
    "128": "img/icon-128.png",
    "256": "img/icon-256.png"
  },
  "permissions": [
    "contextMenus",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "js/context.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "css": [
        "css/youtube.css"
      ],
      "js": [
        "js/youtube.js"
      ],
      "run_at": "document_end",
      "all_frames": false
    },
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "css": [
        "css/twitch.css"
      ],
      "js": [
        "js/twitch.js"
      ],
      "run_at": "document_end",
      "all_frames": false
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{ce4aa23a-d38d-4797-b973-16e0fb382733}"
    }
  }
}