Examine source code of MPT Hide Browser UI

{
  "manifest_version": 2,
  "name": "MPT Hide Browser UI",
  "version": "2",
  "description": "Makes the Browser Open without Browser UI (address bar, toolbar, etc.).",
  "icons": {
    "48": "icons/mpt@48.png",
    "96": "icons/mpt@96.png"
  },
  "browser_action": {
    "default_icon": {
      "48": "icons/mpt@48.png",
      "96": "icons/mpt@96.png"
    },
    "default_title": "MPT Hide Browser UI",
    "default_popup": "html/index.html"
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{2b47bc11-0396-4cdc-8c86-b9f4198df132}"
    }
  }
}