Here's a screenshot of my Windows 8.1 Calendar.
As you can see, some of the items appear lighter/greyed out (ie on the 15th, 21st).
Why is this? I have not noticed any difference between these items, and none of the ideas I've had for why (ie items without a specific time are lighter) have fitted.
My calendar is synced to hotmail.
The calendar online (hotmail.co.uk). (There are a couple of new events, but nothing should have changed with the earlier ones.)
This event appears lighter.
But this event does not.