Examine source code of Spotlight Reader: Text-to-Speech & Highlighting

{
  "manifest_version": 3,
  "name": "__MSG_extension_name__",
  "short_name": "__MSG_extension_short_name__",
  "description": "__MSG_extension_description__",
  "version": "3.0.9",
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "read-aloud-fork@lucaseichhorn",
      "strict_min_version": "121.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "action": {
    "default_popup": "popup.html?isPopup=1",
    "default_icon": {
      "16": "img/icon_toolbar.png",
      "32": "img/icon_toolbar.png",
      "48": "img/icon_toolbar.png"
    }
  },
  "icons": {
    "128": "img/icon.png"
  },
  "permissions": [
    "activeTab",
    "contextMenus",
    "identity",
    "scripting",
    "storage"
  ],
  "optional_permissions": [
    "webRequest",
    "webNavigation"
  ],
  "host_permissions": [
    "https://translate.google.com/"
  ],
  "optional_host_permissions": [
    "http://*/",
    "https://*/",
    "file://*/*"
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self' 'wasm-unsafe-eval'; worker-src 'self'"
  },
  "web_accessible_resources": [
    {
      "resources": [
        "player.html",
        "sound/*",
        "img/*",
        "css/*",
        "js/supertonic-worker.js",
        "js/supertonic-idb.js",
        "lib/onnxruntime/*"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "background": {
    "scripts": [
      "js/rxjs.umd.min.js",
      "js/defaults.js",
      "js/messaging.js",
      "js/content-handlers.js",
      "js/events.js"
    ]
  },
  "options_page": "options.html",
  "options_ui": {
    "page": "options.html"
  },
  "commands": {
    "play": {
      "suggested_key": {
        "default": "Alt+O"
      },
      "description": "Play/Stop"
    },
    "pause": {
      "suggested_key": {
        "default": "Alt+P"
      },
      "description": "Play/Pause"
    },
    "stop": {
      "description": "Stop"
    },
    "forward": {
      "suggested_key": {
        "default": "Alt+Period"
      },
      "description": "Forward"
    },
    "rewind": {
      "suggested_key": {
        "default": "Alt+Comma"
      },
      "description": "Rewind"
    },
    "rate-up": {
      "description": "Speed up (+0.1x)"
    },
    "rate-down": {
      "description": "Slow down (-0.1x)"
    }
  }
}