Examine source code of Tab File Saver

{
  "manifest_version": 2,
  "name": "Tab File Saver",
  "version": "1.0.2",
  "description": "Saves files of specific extensions to a predefined location and closes the tab",
  "permissions": [
    "tabs",
    "downloads",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "icons/icon-19.png",
      "38": "icons/icon-38.png"
    },
    "default_title": "Save File & Close Tab"
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{00c4bf9d-27d8-4a41-b1bd-b9c61048d71d}"
    }
  }
}