Examine source code of Select Text and Read Aloud

{
  "manifest_version": 3,
  "name": "Read Aloud",
  "version": "1.0",
  "description": "Select text on any page and have it read aloud with text-to-speech.",
  "permissions": [
    "contextMenus",
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "action": {
    "default_popup": "popup.html",
    "default_title": "Read Aloud"
  },
  "commands": {
    "read-selection": {
      "suggested_key": {
        "default": "Ctrl+Shift+S"
      },
      "description": "Read the selected text aloud"
    },
    "stop-reading": {
      "suggested_key": {
        "default": "Ctrl+Shift+X"
      },
      "description": "Stop reading"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "read-aloud@example.com",
      "strict_min_version": "115.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}