Examine source code of Selectext: Copy Text from Videos

{
  "name": "__MSG_extension_name__",
  "description": "__MSG_extension_description__",
  "version": "3.1.22",
  "manifest_version": 2,
  "default_locale": "en",
  "icons": {
    "128": "images/selectext-128-icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{88f0c183-636c-43b2-a5eb-f73c26bbc36e}",
      "strict_min_version": "58.0"
    }
  },
  "permissions": [
    "activeTab",
    "storage",
    "browsingData",
    "scripting",
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "polyfills/browser-polyfill.min.js",
        "jquery/jquery-3.5.1.min.js",
        "jquery/jquery-ui.min.js",
        "arrive/arrive.min.js",
        "lodash/lodash.min.js",
        "selectable/selectable.js",
        "common.js",
        "config.js",
        "settingsManager.js",
        "login.js",
        "limit.js",
        "review.js",
        "content.js",
        "shortcut.js",
        "iframeListener.js",
        "screenshot.js"
      ],
      "all_frames": true,
      "run_at": "document_end"
    },
    {
      "matches": [
        "*://*.selectext.app/*"
      ],
      "js": [
        "polyfills/browser-polyfill.min.js",
        "siteListener.js"
      ],
      "all_frames": true,
      "run_at": "document_start"
    }
  ],
  "browser_action": {
    "default_title": "selectext",
    "default_icon": "images/selectext-128-icon.png",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "polyfills/browser-polyfill.min.js",
      "config.js",
      "background.js"
    ]
  },
  "web_accessible_resources": [
    "images/image.svg",
    "images/copy.svg",
    "images/camera.svg",
    "images/selectext-logo-filled.svg",
    "fonts/open_sans/open-sans-v18-latin-800.woff",
    "fonts/open_sans/open-sans-v18-latin-regular.woff",
    "fonts/open_sans/OpenSans-Bold.woff",
    "login.html",
    "limit.html",
    "review.html",
    "shadow.css",
    "login.css",
    "images/google-logo.svg",
    "images/microsoft-logo.svg",
    "images/email-icon.png"
  ],
  "commands": {
    "copy-text-from-video": {
      "suggested_key": {
        "default": "Alt+S"
      },
      "description": "Copy Text from Video"
    }
  }
}