Examine source code of Price rounder

{
  "manifest_version": 2,
  "name": "Price rounder",
  "version": "1.0.1",
  "description": "Round up psychological pricing to its nearest whole value, revealing the true cost of items on selected websites. Supports a wide range of currencies, including € $ £ ¥ ₹ ₩ ₽ ₺ ₪ ₦ ৳ ₱ ₨.",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_script.js"
      ]
    }
  ],
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "An error occurred while trying to open the popup",
    "default_popup": "popup/popup.html"
  },
  "options_ui": {
    "page": "options/options.html"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{064787e0-f655-4a2b-8829-6879ced91404}"
    }
  }
}