Undoing changes in the Animator throws an error

Repro:
Create a new Animator Controller
1. Add a parameter
2. Create a new layer
3. Add another parameter
4. change something in the layer (weight/blending/synch)
5. Undo a couple of changes . the error pops up: Unhandled alignment handling

This only happens - so far - if the undone changes were a mix between adding parameters, and changes done to the layer.