Crash with Staff-type change
1) Create score + add a staff type change on first system
2) Update its properties (1-line, offset to center for example I used)
3) Place another staff-type change on next measure and update its properties to something different
4) Now [Ctrl+Drag] the second staff type change and bring it to the previous measure which has the first staff type change.
5) Delete the first staff type change
Notice that there's still a staff type change (the ctrl+drag didn't replace but added another one some how)
6) select and delete this.
Crash. File included with similar steps. Consider it critical due to crashing