How to reproduce:
1. Open the project
2. Make a Windows x86_64 release build.
3. Wait for the build to finish.
4. Run the built version.
5. Press "Play and host"
6. Go to Unity and press Play.
7. Wait for the project to run and press "Join" at the bottom of the screen.
8. Press "Join" on the next screen.
9. Go to the built version and press "Join".
10. Wait for the game to run.
12. Move using WASD.
13. Notice in Unity that "Built Player" doesn't move.

Actual results: Clients in Multiplayer games don't see anyone moving
Expected results: Clients in Multiplayer games see all the movements

Reproducible with: 2018.3.1f1
Not reproducible with: 2017.4.18f1

Regressed in: 2018.2.19f1

Not tested with 2019 because NetworkLobbyManager is obsolete there