Examine source code of Trigonometry Toolbox

{
  "manifest_version": 2,
  "name": "Trigonometry Toolbox",
  "version": "1.0",
  "description": "Here, we have to give an angle in degrees as input in the input box and it calculates the corresponding value of the given angle. The application is user-friendly users can easily find the trigonometric values. There is validation if the user doesn’t enter any value and clicks on the calculate button then the message would appear as Please enter a valid angle.",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/tool-logo.png"
    }
  },
  "icons": {
    "128": "images/tool-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8f8898c3-6cd9-4cbb-b380-a9b9f988731c}"
    }
  }
}