Determines what happens when you click a parent drawer that was did not already have keyboard focus. In addition to becoming the focused control, should its unfolded state also be altered with the first click?

True

Always toggle the unfolded state of parent drawers when they are clicked, even if they did not have keyboard focus before the click event.
This option makes it easier to select parent drawers without also unfolding them as an unintended side effect.
This option allows you to change the unfolded state of parent drawers a bit more easily without needing to click the foldout icon or having to click twice.

False (Default)

Don’t toggle the unfolded state of parent drawers when being selected with the left mouse click.
Only alter the unfolded state when an already selected parent drawer is clicked again, or if the foldout icon is clicked specifically.
This option makes it easier to select parent drawers without altering their unfolded state as an unintended side effect.