Use the helper-text attribute or add content to the helper slot to set helper content.
The step property specified in seconds affects the resolution of the time picker and visibility of the time picker dropdown. If step is less than 15 minutes (<900) the dropdown is hidden.
The min and max properties affect the range of dates and times that will be available in the picker.
Note: The date time picker has a non-empty value only when both a date and a time have been selected.
Dropdown is only opened when clicking the toggle button or pressing Up or Down arrow keys.