Regression: Crash when pressing tie key in real-time mode with MIDI input/Piano keyboard
Steps to reproduce:
1. Enter a note in real-time mode (manual or automatic)
2. Press the Tie key (+)
Crash. (version 2.1.0-RC on Windows 10)
(Expected: last entered note is extended by the currently selected duration.)
Note that the crash does not occur if the user presses Left before tying, i.e. to select the last entered note.