Examine source code of Speed It Up

{
  "name": "Speed Up",
  "description": "A simple extension to control playback speed of media elements on a webpage.",
  "version": "1.0",
  "manifest_version": 3,
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon.png",
      "48": "icons/icon.png",
      "128": "icons/icon.png"
    }
  },
  "icons": {
    "16": "icons/icon.png",
    "48": "icons/icon.png",
    "128": "icons/icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "speedup@example.com",
      "strict_min_version": "109.0"
    }
  }
}