Examine source code of Text to Speech

{
  "manifest_version": 3,
  "name": "Text to Speech",
  "description": "Read text aloud by clicking or selecting. Simple usage and settings.",
  "version": "1.1",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "action": {
    "default_icon": {
      "16": "tts-icon.png",
      "32": "tts-icon.png",
      "48": "tts-icon.png",
      "128": "tts-logo.png"
    },
    "default_popup": "popup.html"
  },
  "icons": {
    "16": "tts-icon.png",
    "32": "tts-icon.png",
    "48": "tts-icon.png",
    "128": "tts-logo.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{e11c77e8-87b4-466a-a835-266fec7bd5ee}"
    }
  }
}