Examine source code of ZenPocket

{
  "manifest_version": 2,
  "name": "ZenPocket",
  "version": "1.0.0",
  "description": "Save articles, web pages, and videos to read later in a zen-like, distraction-free environment",
  "permissions": [
    "storage",
    "tabs",
    "activeTab",
    "contextMenus",
    "bookmarks",
    "downloads",
    "notifications",
    "<all_urls>"
  ],
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ]
    }
  ],
  "commands": {
    "save-page": {
      "suggested_key": {
        "default": "Ctrl+Shift+S",
        "mac": "Command+Shift+S"
      },
      "description": "Save current page to ReadItLater"
    }
  },
  "web_accessible_resources": [
    "reader.html",
    "css/*",
    "js/*",
    "icons/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "zenpocket@example.com",
      "strict_min_version": "58.0"
    }
  }
}