Examine source code of Simple Number Converter

{
  "manifest_version": 2,
  "name": "Simple Number Converter",
  "version": "1.0",
  "description": "Supports binary, octal, decimal, and hexadecimal.",
  "homepage_url": "https://github.com/kokhong1995/number-converter-web-extension.git",
  "icons": {
    "48": "icons/number-converter-web-extension-48.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/number-converter-web-extension-32.png",
    "default_title": "Number Converter",
    "default_popup": "popup/main.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "kokhong.hean@gmail.com"
    }
  }
}