The issue occurs due to the difference in the z-index value of the Window and the Popup of the DatePicker.
The following CSS will fix it:
z-index: 99 !important;
z-index: 10005 !important;
I noticed another issue when the icon in the DatePicker is clicked that will not close it. This is due to the Window getting the focus.
We are working on the native Window component that is already in the test stage, and we can recommend waiting for it if it is possible.
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