Examine source code of ReadX Text To Speech

{
  "manifest_version": 2,
  "name": "ReadX Text To Speech",
  "version": "1.0.9",
  "description": "Text to speech Extension",
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "images/get_started16.png",
      "32": "images/get_started32.png",
      "48": "images/get_started48.png",
      "128": "images/get_started128.png"
    }
  },
  "permissions": [
    "activeTab",
    "storage",
    "webNavigation",
    "tabs"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "all_frames": true,
      "match_about_blank": true
    }
  ],
  "commands": {
    "activateextension": {
      "suggested_key": {
        "default": "Ctrl+Shift+O"
      },
      "description": "Activate the extension"
    }
  },
  "icons": {
    "16": "images/get_started16.png",
    "32": "images/get_started32.png",
    "48": "images/get_started48.png",
    "128": "images/get_started128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ce6e1d02-1369-4f20-a7df-4ee8a8e6c7c9}"
    }
  }
}