Numpad keys don't respond to input commands on Linux

Setting any of the numpad keys to an input command does not execute the command on Linux.

1. Open UE4Editor (any project)
2. Create Blueprint based on Actor (MyActor_BP)
3. In MyActor_BP set Auto Receive Input to Player 0
4. In event graph, add Num0 event and wire into Print String node
5. Compile/save BP
6. Place BP instance into level
7. PIE and press numpad 0

Result:
Print String node does not print in game

Expected:
Using numpad events functions the same as using other keys.