Examine source code of Auto Zoom by Time

{
  "manifest_version": 2,
  "name": "Auto Zoom by Time",
  "version": "1.0",
  "description": "Automatically set page zoom depending on time: morning ~100%, late night ~120%.",
  "icons": {
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{fddbf4ac-4b55-465e-8b3b-b73859177b76}"
    }
  }
}