Units spawned while editing In-Game disappear completely when reentering the map in any capacity

[UntotenTheo]

Title should be mostly self-explanatory.

How to Replicate Bug:

1. Load 'Scheme Size' or 'Testing Utilities' mod, alternatively, use Console
2. Spawn a unit, any unit, Vanilla/Modded doesn't matter
3. Exit In-Game Editor, reenter In-Game Editor or swap to Playtest mode
4. Done, the units you spawned are absent.