Not quite a bug, but intuitively, I assumed that when opening the due date panel, I could:

1. immediatly start typing the date

2. press enter once to choose

3. press enter again to confirm/close the panel.

It doesn't close the panel (#3) when 'enter'ing again

Also, there's a teeny tiny lag when typing, for example, Today, and then being able to choose it (#2), so I click enter twice to select(because it hasn't loaded untilt he second click)- but then again, I'm a fast typer.