Lichess.org chat/whisper with move numbers

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Lichess.org chat/whisper with move numbers",
  "version": "2021.03.14",
  "description": "Send chat messages or whisper to spectators room with move numbers",
  "content_scripts": [
    {
      "css": [
        "styles.css"
      ],
      "js": [
        "content.js"
      ],
      "matches": [
        "https://lichess.org/*"
      ]
    }
  ],
  "permissions": [
    "storage"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "icons": {
    "128": "icon128.png"
  },
  "applications": {
    "gecko": {
      "id": "Lichess_Chat_Whisper_Move_Numbers"
    }
  }
}