Examine source code of Rohlik Score

{
  "manifest_version": 3,
  "name": "RohlikHealth",
  "version": "1.0.0",
  "description": "Adds Nutri-Score health ratings to every product on rohlik.cz",
  "permissions": [
    "storage",
    "tabs"
  ],
  "host_permissions": [
    "*://*.rohlik.cz/*",
    "*://world.openfoodfacts.org/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.rohlik.cz/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    },
    "default_title": "RohlikHealth"
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "rohlikhealth@extension",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}