Examine source code of Speed & Pace Calculator

{
  "manifest_version": 2,
  "name": "Speed & Pace Calculator",
  "version": "1.0",
  "description": "Calculate your average speed and time per kilometer to improve your running performance.",
  "permissions": [],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "128": "images/speed-logo.png"
    }
  },
  "icons": {
    "128": "images/speed-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{09ff3d2d-a92e-474d-a832-38e1d66eb693}"
    }
  }
}