[Mac] Alt has no effect for lyric skipping

1. Open attached score (produced in 1.3).
2. Double-click just before the "L" of the first lyric (in order to place the cursor at the start).
3. Hold Alt and press Right.

Expected result: The next lyric is highlighted.
Actual result: The cursor moves to the next character.

Notes:

It is reproducible in a 2.0 score.
It only seems to affect Mac.

Using MuseScore 2.0 Nightly Build fa0f99b - Mac 10.7.5.