Toolbar partially non-functional after changing value

1. Create score.
2. Enter crotchet.
3. Click on it.
4. Using the keyboard shortcut, change the value to a quaver.

Result: After step four, the majority of toolbar buttons are greyed out.

Workaround: Re-click the note.

Using MuseScore 2.0 Nightly Build (4303) - Mac 10.4.11.