Examine source code of Zebra Printing

{
  "manifest_version": 3,
  "name": "Zebra Printing",
  "version": "1.7",
  "description": "Allows to print ZPL to a network connected Zebra printer.",
  "icons": {
    "128": "zebra128.png"
  },
  "author": "Daniel Nitz",
  "browser_specific_settings": {
    "gecko": {
      "id": "{885527f4-6ae3-4b5e-94d5-a11cbd83c6ad}",
      "strict_min_version": "135.0"
    }
  },
  "permissions": [
    "activeTab"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "service_worker": "background.js"
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self';"
  },
  "action": {},
  "offline_enabled": true
}