Expected behaviour

We are using attribute orientation auto. We know that it's the default attribute. We have a fixed header. It's features : z-index: 9996 and height: 25px.

We are using datepicker in a lot of areas. The datepicker changes direction at critical places between Window Top and the datepicker and there is a z-index problem. I added an example of jsfield.
Steps:
Click input and months, you see the issue. Or you can try according to the steps of the following image.

Actual behaviour

For Calculation:

• We can add a fixed height for the top or bottom(for us just top) if there is. And dates, months, years, decades, and centuries should have the same heights for just calculations.

Datepicker version used

v1.9.0

Example code

You can check the issue in here:
https://jsfiddle.net/u5fjw6vo/2/