Examine source code of OpenTab

{
  "manifest_version": 2,
  "name": "OpenTab",
  "version": "0.2",
  "description": "A simple but functional new tab replacement with quick access to recently closed tabs",
  "developer": {
    "name": "Matt Krins",
    "url": "https://github.com/mattkrins/"
  },
  "icons": {
    "16": "img/icons/icon-16.png",
    "32": "img/icons/icon-32.png",
    "48": "img/icons/icon-48.png",
    "96": "img/icons/icon-96.png",
    "256": "img/icons/icon-256.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "permissions": [
    "storage",
    "sessions",
    "tabs"
  ],
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{869dad27-5e76-41c2-977d-8edbcb6f3516}",
      "strict_min_version": "57.0"
    }
  }
}