Reproduction steps:
1. Open the attached project in Unity
2. Open the "Scene" scene
3. Build and run
4. Wait till it says "Initialized (server)" on the built project
5. Enter Play mode in the editor

Result1: Broadcast data on the My Network Discovery changes from "HELLO" to "NetworkManager:LocalHost:7777"
Result2: Note how in the Console it says "data == this.broadcastData: False", this is due to sent data being 29 char long, while the received data is 512 char long.

Reproducible on: 5.4.3f1, 5.5.0f3, 5.6.0a6 versions of Unity.