Examine source code of Bootstrap Stopwatch Basic

{
  "manifest_version": 2,
  "name": "Bootstrap Stopwatch Basic",
  "version": "1.0",
  "description": "A stopwatch tracks elapsed time, typically in hours, minutes, seconds, and fractions of a second. It can be started, stopped, and reset",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/boot-logo.png"
    }
  },
  "icons": {
    "128": "images/boot-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{bc943f72-10d6-4fe3-b6b4-e4aa92c25353}"
    }
  }
}