Examine source code of Camel Letter App

{
  "name": "Camel Letter App",
  "manifest_version": 2,
  "version": "1.3",
  "description": "Transforme as letras de uma palavra ou frase em maiúsculas ou minúsculas e seja feliz! 😁",
  "author": "Van Ribeiro",
  "browser_action": {
    "default_popup": "popup/camellettersapp.html",
    "default_title": "Camel Letters App"
  },
  "icons": {
    "16": "img/icons/camel16.png",
    "32": "img/icons/camel32.png",
    "48": "img/icons/camel48.png",
    "128": "img/icons/camel128.png"
  }
}