Examine source code of Tamper Data Classic

{
  "manifest_version": 2,
  "name": "Tamper Data",
  "version": "2.1.0",
  "description": "View and modify HTTP/HTTPS headers and POST data. Modern rewrite of the classic extension.",
  "author": "Original: Adam Judson, Modern rewrite: Claude",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "<all_urls>",
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "js/background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/icon-48.png"
    },
    "default_title": "Tamper Data"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "tamperdata-modern@example.com",
      "strict_min_version": "58.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}