C++ Third Person Template does not accept input for server character in PIE

When testing network multiplayer in PIE, server character does not respond to input and cannot be controlled.

1. Open UE4 Editor (C++ Third Person Template project)
2. In Play drop-down, set Number of Players to 2
3. PIE
4. Switch to Server character (in the editor viewport)
5. Use WASD and mouse to move character

Result:
Character does not respond to any input