Examine source code of TabletNav

{
  "manifest_version": 2,
  "name": "TabletNav",
  "version": "1.0",
  "description": "Switch tabs by swiping down from the top of the screen, go back and forwad in history of the window and jump between tabs",
  "permissions": [
    "tabs",
    "storage",
    "activeTab",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": "favicon-48x48.png",
    "default_title": "TabletNav"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "style.css"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "icons": {
    "16": "icons/favicon-16x16.png",
    "32": "icons/favicon-32x32.png",
    "48": "icons/favicon-48x48.png",
    "64": "icons/favicon-64x64.png",
    "128": "icons/favicon-128x128.png",
    "192": "icons/favicon-192x192.png",
    "512": "icons/favicon-512x512.png"
  },
  "applications": {
    "gecko": {
      "id": "TabletNav@example.com",
      "strict_min_version": "58.0"
    }
  }
}