Examine source code of Quick Tabs Ported

{
  "version": "1.0.6",
  "name": "Quick Tabs Ported",
  "manifest_version": 2,
  "description": "Ported version from the Chrome extension Quick Tabs, with a few small tweaks.  Chrome description reads:  'A keyboard centric most recently used (MRU) ordered tab list plugin with search and switch functionality inspired by IntelliJ IDEA'",
  "applications": {
    "gecko": {
      "id": "quicktabs@quicktabs.org"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "assets/icon-32.png",
    "default_title": "Quick Tabs",
    "default_popup": "popup.html"
  },
  "icons": {
    "32": "assets/icon-32.png",
    "48": "assets/icon-48.png",
    "128": "assets/icon-128.png"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "permissions": [
    "tabs",
    "bookmarks",
    "history"
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+E",
        "mac": "Command+Shift+E"
      },
      "description": "Open app in browserAction popup"
    },
    "quick-prev-tab": {
      "description": "Previous tab"
    },
    "quick-next-tab": {
      "description": "Next tab"
    }
  }
}