**System Information**
Windows 7
Nvidia Geforce GT620
**Blender Version**
2.79, Steam, latest
**Short description of error**
When hitting Undo after, say, the Y axis mirror, hitting Ctrl+Z does not undo the operation.
**Exact steps for others to reproduce the error**
Based on a (as simple as possible) attached .blend file with minimum amount of steps
Simply go to Tools -> Automirror -> Options -> Y -> hit button -> Ctrl+Z{F1041058}