Examine source code of History Helper

{
  "manifest_version": 3,
  "name": "History Helper",
  "version": "1.3.0",
  "description": "A history viewer.",
  "author": "J.C. Fields",
  "homepage_url": "https://github.com/jcfieldsdev/history-helper",
  "permissions": [
    "history",
    "storage"
  ],
  "icons": {
    "16": "icons/icon-neutral.svg",
    "32": "icons/icon-neutral.svg",
    "48": "icons/icon-neutral.svg",
    "64": "icons/icon-neutral.svg"
  },
  "background": {
    "scripts": [
      "service-worker.js"
    ]
  },
  "action": {
    "default_icon": "icons/icon-dark.svg",
    "theme_icons": [
      {
        "light": "icons/icon-light.svg",
        "dark": "icons/icon-dark.svg",
        "size": 16
      },
      {
        "light": "icons/icon-light.svg",
        "dark": "icons/icon-dark.svg",
        "size": 32
      }
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2c97aa17-6119-4d7a-81cc-4de93d8b779e}"
    }
  }
}