Examine source code of Prime Number Finder Basic

{
  "manifest_version": 2,
  "name": "Prime Number Finder Basic",
  "version": "1.0",
  "description": "We’ll develop a basic web application that will take user input and will determine whether the entered number is prime or not.",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/number-logo.png"
    }
  },
  "icons": {
    "128": "images/number-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7ab04bf4-7a5b-4dc9-a2ec-da231208a14d}"
    }
  }
}