New unit Xeno drone lost?

[Wildfire]

Raided a ruin, and received a Xeno drone as a unit. Moved unit 3 turns and it is gone now... didn't see it lost, not sure where it went. Didn't save after I received it, and not at war with any factions yet (still early game October 2107 when I realized it was missing - maybe last 15 - 20 turns it's gone.

[Wildfire]

Version 16.0 - Have had 3 other units lost as well while having them attack. See if you all can recreate it as well. It takes a few seconds to do the attack motion and sounds, but stack a few units or have them in the next hexes over, and quickly click on units and have them attack a target, then before the combat motion is complete, click on the next unit and tell it to attack. Typically I've had 2-3 first level infantry stacked and have lost 1, have also lost a first tier flying unit this way.