Undo of stretch results in notes displaying on wrong line, missing clefs changes

Windows 7, GIT commit: d8b325d

See #25394: Reducing stretch corrupts (?) score with clef change. That bug was fixed, however, Undo fails.

1) open the same score as used in the above and follow the same steps
2) now Undo once

Result: looking at measures 9-12, we see similar symptoms as before: notes are displayed according to the wrong clef. In this case, the real clef is treble but they are displayed as if they were in bass clef.

Also, no courtesy clef appears appears in the bottom staff before measure 13.

Undo again and now no clef change appears at all before measure 13.

The issue with the clefs makes me think there is something going on other than the line computation, but whether this is two separate issues or not I cannot say.