Examine source code of Square Root Calculator

{
  "manifest_version": 2,
  "name": "Square Root Calculator",
  "version": "1.0",
  "description": "Calculates the square root of a number",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_icon": {
      "48": "icon.png"
    },
    "default_title": "Square Root Calculator",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e4b3fad9-a86f-4064-b96d-820920dc0f91}"
    }
  }
}