Examine source code of Streamer Calculator

{
  "manifest_version": 3,
  "name": "Streamer Calculator",
  "short_name": "Streamer Calculator",
  "version": "1.0.0",
  "description": "Creator earnings calculators for YouTube, Twitch, TikTok, and more from StreamerCalculator.com.",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "homepage_url": "https://www.streamercalculator.com/",
  "browser_specific_settings": {
    "gecko": {
      "id": "spacesite@streamercalculator.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "action": {
    "default_popup": "popup/popup.html",
    "default_title": "Streamer Calculator",
    "default_icon": {
      "16": "icons/icon16.png",
      "24": "icons/icon24.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}