The new default dates were not aligned with the assumption that the
datepicker would open on the current date. The datepicker helper would
try to navigate to the previous month or next month in relation to the
reference date. Now with the wrong reference date, it would infinitely
go into the past or future, not finding the right year and month.
I chose a more robust approach of setting the year and month directly
which the user can do as well. Then we don't need a reference date.
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