Gap between arrow and the datepicker

[AHorak]

Describe the bug
If the arrow is below the input field, i can see this small gap of 1 px.
Tested with Firefox 125.0.3 on Windows 10 Desktop
Works with Chrome 124

To Reproduce
Go to page https://reactdatepicker.com/#example-default

Screenshot:

[AHorak]

Looks better om Chrome or Edge