Examine source code of Font Picker

{
  "name": "Font Picker",
  "short_name": "FP",
  "description": "A simple helper to identify font details from any website",
  "version": "1.0.5",
  "author": "Paul Krishnamurthy",
  "permissions": [
    "contextMenus",
    "http://*/*",
    "https://*/*",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "manifest_version": 2,
  "icons": {
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "browser_action": {
    "default_icon": "icons/icon128.png",
    "default_title": "Font Picker",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/jquery.min.js",
        "js/sweetalert.min.js",
        "js/content.js"
      ],
      "css": [
        "styles/sweetalert.css",
        "styles/custom.css"
      ]
    }
  ],
  "web_accessible_resources": [
    "logo.png",
    "background.png"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f4b3335b-382b-4a5f-a9d1-33cb58e41337}"
    }
  }
}