Undo adding instrument to score leads to crash
In an existing score add an instrument using the instruments dialog. Click the undo button and the result is a crash.
Submitting crash report referencing this issue.
The score that crashed was created in version 2.3.2. Creating a similar score in 3.0.5 did not immediately cause a crash, so I'll do some more testing. Perhaps feedback from the crash report could tell where to look.