It appears that Microsoft is intentionally removing some features from the Windows 11 taskbar in order to push widgets.
Windows 11 Taskbar Customization Tutorial
Windows Latest reports that despite initial hopes that the missing taskbar features in Windows 11 were just a bug, Microsoft has confirmed that they are intentional. The aim is to encourage people to use the Windows Widgets panel instead.
The Windows 11 calendar popup is one of the most notable changes, as it no longer integrates with events or calendars. Opening the calendar from the Windows 11 taskbar displays dates, but does not allow you to add new events. On the Windows Feedback Hub, Microsoft stated that "…there is a calendar option in the new widgets experience that you can use to quickly view your personal calendar and events."
The clock has also been tweaked so that it no longer displays the time in seconds when clicked. Microsoft says you can add up to two different clock displays to the taskbar popup, but admits that showing seconds is not supported.
