Examine source code of Simple PDF V2

{
  "manifest_version": 2,
  "name": "Simple PDF V2",
  "version": "1.3",
  "description": "A simple PDF viewer extension with extended features.",
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "viewer.html",
    "default_icon": "icons/logo_64.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*.pdf"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{24f29b8e-b744-4217-b67a-6701d3267996}"
    }
  }
}