Examine source code of Max Tabs (Web Extension)

{
  "manifest_version": 2,
  "name": "Max Tabs (Web Extension)",
  "short_name": "Max Tabs",
  "version": "0.1.1resigned1",
  "description": "Set maximum number of opened tabs in a window.",
  "default_locale": "en",
  "icons": {
    "48": "icons/icon-48.png"
  },
  "author": "Kan-Ru Chen",
  "homepage_url": "https://github.com/kanru/max-tabs",
  "incognito": "spanning",
  "background": {
    "scripts": [
      "lib/chroma.js",
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true
  },
  "browser_action": {
    "browser_style": true,
    "default_icon": "icons/icon.svg",
    "default_title": "Max Tabs"
  },
  "permissions": [
    "notifications",
    "storage"
  ],
  "applications": {
    "gecko": {
      "id": "max-tabs@kanru"
    }
  }
}