O mesmo suporte,
dentro do seu aplicativo

<!-- antes do </body> -->
<script>
  (function (w, d) {
    w.bFocusQueue = w.bFocusQueue || [];
    w.bFocus = w.bFocus || { init: function(o){ w.bFocusQueue.push(['init', o]); } };
    var s = d.createElement('script');
    s.async = true; s.src = 'https://widget.bfocus.com.br/v1/widget.js';
    s.setAttribute('data-bf-key', 'bf_pk_…');
    d.head.appendChild(s);
  })(window, document);
  bFocus.init({
    user:     { externalId: 'USR-123', name: 'João Silva' },
    customer: { externalId: 'EMP-456', name: 'Empresa Ltda' },
    userHash: '…'   // assinado no SEU servidor
  });
</script>

Widget web — no ar, servido pela CDN

# Flutter — pubspec.yaml
bfocus_widget: ^0.1.0

// iOS — Package.swift (produtos BFocusWidget e BFocusWidgetCore)
.package(url: "https://github.com/bernisoftware/bfocus-widget-ios", from: "0.1.2")

// Android — build.gradle.kts (para Compose: bfocus-widget-android-compose)
implementation("br.com.bernisoftware:bfocus-widget-android:0.1.0")

# React Native
$ npm i @bfocus/react-native-widget react-native-webview @react-native-async-storage/async-storage

# .NET — ou Bfocus.Widget.Wpf / Bfocus.Widget.Maui
$ dotnet add package Bfocus.Widget.WinForms

// Java desktop — ou bfocus-widget-swing
implementation("br.com.bernisoftware:bfocus-widget-javafx:0.1.0")

# Delphi
$ boss install github.com/bernisoftware/bfocus-widget-delphi

# Lazarus — depois abra package/bfocus_widget_lcl.lpk
$ git clone https://github.com/bernisoftware/bfocus-widget-lazarus

# Python desktop — ou [tk]
$ pip install "bfocus-widget[qt]"

Um comando por plataforma. A chave publicável é a mesma em todas.

# pubspec.yaml
dependencies:
  bfocus_widget: ^0.1.0

import 'package:bfocus_widget/bfocus_widget.dart';

await BFocus.init(BFocusConfig(
  publishableKey: 'bf_pk_…',
  user: BFocusUser(externalId: u.id, name: u.nome),
  customer: BFocusCustomer(externalId: u.empresaId),
  userHashProvider: () => minhaApi.bfocusUserHash(),
  navigatorKey: navigatorKey,
  product: 'erp',              // opcional: marca do produto
));

Pacote bfocus_widget 0.1.0, publicado no pub.dev

// Flutter: o selo acompanha o estado do widget
ValueListenableBuilder<String>(
  valueListenable: BFocus.badge,          // '' | '•' | 'N' | '99+'
  builder: (context, label, _) => Badge(
    isLabelVisible: label.isNotEmpty,
    label: Text(label),
    child: IconButton(
      icon: const Icon(Icons.support_agent),
      onPressed: () => BFocus.open(context: context),
    ),
  ),
);

O contador de não lidos é reativo: você o desenha onde quiser