Activity Diagram ommits days without activity

When viewing the activity diagrams days without commits are ommited, i.e. I can't see days where someone has been unproductive.

Example: Two bars next to each other have the dates 01.06 and 20.06, with 18 days of inactivity inbetween. In the diagramm these days are not shown.

Is there a way to enable this?

Cheers,
uvwxy