Examine source code of Web Developer Tools Lite

{
  "manifest_version": 2,
  "name": "Web Developer Tools Lite",
  "version": "1.0.0",
  "description": "Lightweight web developer tools: outline elements, show images, and display meta information.",
  "permissions": [
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "Blo.g.sM.a.ti.z@gmail.com",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}