Examine source code of Internal Link Collector

{
  "manifest_version": 2,
  "name": "Internal Link Collector",
  "version": "1.0",
  "description": "A Firefox extension that collects internal links from the current page.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_icon": {
      "48": "icon.png"
    },
    "default_popup": "popup.html"
  },
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{1c7d6474-cb0d-444e-b7f3-d17a2fa58c9e}"
    }
  }
}