MarkedTimespan in month view

I am adding a full day marked timespan as such

days: new Date(year, month - 1, day),
zones: “fullday”,
css: “dhx_date_unavailable”,
html: “No staff scheduled”

If the day of the month has a lot of events and is extended the timespan doesn’t draw properly. See the attached image.


The issue isn’t reproduced:
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