Examine source code of External Links Bold

{
  "manifest_version": 2,
  "name": "External Links Bold",
  "version": "1.0",
  "description": "Bold external links on webpages.",
  "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": "{f33d0a1b-c9c1-4eda-8f30-501e5874d103}"
    }
  }
}