Examine source code of FramelessApp Ext

{
  "manifest_version": 2,
  "author": "Isaac Penrod",
  "homepage_url": "https://www.framelessapps.com/extension.html#extension",
  "name": "FramelessApp Ext",
  "version": "0.1.3resigned1",
  "description": "Launch your current tab as a FramelessApp",
  "default_locale": "en",
  "icons": {
    "16": "assets/fl-icon-16.png",
    "32": "assets/fl-icon-32.png",
    "48": "assets/fl-icon-48.png",
    "96": "assets/fl-icon-96.png"
  },
  "permissions": [
    "activeTab",
    "contextMenus",
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "content/background/background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "assets/fl-icon-16.png",
      "32": "assets/fl-icon-32.png",
      "48": "assets/fl-icon-48.png",
      "96": "assets/fl-icon-96.png"
    },
    "default_title": "FramelessApp Ext",
    "default_popup": "content/button/panel.html"
  },
  "options_ui": {
    "page": "content/settings/settings.html",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{94b8e6dc-eb82-41ae-b9ee-b548b21ed8b6}"
    }
  }
}