Examine source code of Watermark image generator

{
  "manifest_version": 3,
  "name": "Watermark image generator",
  "version": "1.0",
  "description": "Watermark image generator (jpg / jpeg / png)",
  "browser_specific_settings": {
    "gecko": {
      "id": "{2209b380-26de-4475-96c0-a2045387a791}"
    }
  },
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "type": "module"
  },
  "action": {
    "default_title": "Watermark image generator"
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; img-src 'self' data:; object-src 'none'"
  }
}