Examine source code of keltrans Launcher

{
  "manifest_version": 2,
  "name": "keltrans Launcher",
  "description": "Quick launch for KelTrans employees",
  "version": "1.2.5",
  "icons": {
    "128": "icon_128.png"
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "keltrans.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{59d0f515-8669-45af-b9d0-7a52f16b939a}"
    }
  }
}