Cursor jumps to end of input field on up/down keys #45

I don't know if this is a bug or I'm missing something. But I can't get the arrow keys up/down to work properly. When I select the minutes (mm) and press key up it jumps to the end of the input field (after increasing the minute-value by one). The cursor doesnt jump in your demo, it stays and I can increase a value multiple times.

This is what I do:

<input type="text"
    ng-model="thingy.timeModel"
    datetime="mm:ss">