Colors on action item checkbox

The action items have a hollow circle on the right, for checking when the action is done. It’s usually solid yellow on my screen. I just noticed that one of mine is half yellow and half orange, with a little orange wedge in the upper right hand corner. What do these colors mean? What does the wedge mean? (I’ll bet it’s a useful feature than I just never noticed before).

The yellow means that the task is due soon. You can set the due soon preference in the Settings or Preferences screen.

If it is orange, it is a flagged task. The little wedge in the corner is a flag switch. You can click on that wedge to flag or unflag a task without going to the inspector panel.

If the wedge is hollow, it means the container (the project or action group) is flagged.