Examine source code of Visit site

{
  "name": "Visit site",
  "version": "0.0.1",
  "description": "Visit a site in a small window!",
  "manifest_version": 2,
  "icons": {
    "16": "assets/image/logo16.png",
    "32": "assets/image/logo32.png",
    "64": "assets/image/logo64.png",
    "128": "assets/image/logo128.png"
  },
  "browser_action": {
    "default_popup": "index.html",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{50c6d0bc-5825-4a69-a452-1da2c9d78298}"
    }
  }
}