[Python] FastAPI WebSocket + Kafka: Only the last connected client receives messages

I'm building a real-time dashboard using FastAPI WebSockets + Kafka. Everything works perfectly for a single user, but when multiple users connect, only the most recently connected user receives messages.

The behavior:

• First user opens dashboard - receives alerts ✓
• Second user opens dashboard - first user stops receiving, only second user gets messages
• Second user closes connection - first user suddenly starts receiving again

It seems like Kafka messages are only going to one WebSocket connection at a time instead of broadcasting to all connected clients.

Has anyone encountered this? What's the correct way to handle multiple WebSocket clients consuming from the same Kafka topic?

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