Key Signature Crash Bug

When a key is changed, either from a drag/drop from the palette OR a drag and drop from keyboard shortcut K OR from double-clicking the desired key from keyboard shortcut K, applying ctrl+z/undo changes the key to C Maj, not the previous key. Also, when the original key is restored, and ctrl+z/undo is applied, MuseScore shuts down unexpectedly. This crash does not happen when the measure is changed to any other keys but the original.