Examine source code of YoutubeDL-Material

{
  "manifest_version": 2,
  "name": "YoutubeDL-Material",
  "version": "0.6",
  "description": "The Official Firefox & Chrome Extension of YoutubeDL-Material, an open-source and self-hosted YouTube downloader.",
  "browser_action": {
    "default_icon": "favicon.png",
    "default_popup": "popup.html",
    "default_title": "YoutubeDL-Material"
  },
  "permissions": [
    "tabs",
    "storage",
    "contextMenus"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "IsaacMGrynsztein@gmail.com",
      "strict_min_version": "57.0"
    }
  }
}