Pitches incorrect after inserting measures before key signature/clef change

Windows 7, GIT commit: c67a0ae

Seems I remember seeing something like before, but I can't find a current open issue:

1) open attached score
2) click measure 4 (the one containing the Bb)
3) press Insert to insert a measure
4) click the newly inserted measure 4
4) start entering notes: N 7 B B

Result: the second B entered (in what is now measure 5) sounds as a B natural, even though the key signature is still Bb major.

Apparently MuseScore is still remembering the fact that measure 5 formerly (before the measure insert) had a G major key signature.