Examine source code of Sheet Embed by zen-tables

{
  "manifest_version": 2,
  "name": "Sheet Embed by zen-tables",
  "version": "1.0.2",
  "description": "Turn any Google Sheet into a beautiful styled table you can embed on any website. Free to install.",
  "permissions": [
    "tabs",
    "https://docs.google.com/spreadsheets/*"
  ],
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://docs.google.com/spreadsheets/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    },
    "default_title": "Sheet Embed by zen-tables"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "sheetembed@zen-tables.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}