Datepicker: Selection of multiple

I'm designing a web management software that requires users to indicate their work days. These users do not have regular work days and hence we decided to allow them to just pick their work days from a calendar.

They typically select about 20 days out of the whole month (no regular pattern).

How can we show their selections on the text field without having to open the calendar again?

I'm currently thinking either showing:

  1. The count of dates selected
  2. All the dates selected but truncated based on width of field + tooltip to show all dates selected. However I imagine the tooltip can get quite long...

Anyone has any ideas? :/

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