Exporting checkbox values

In a field type of Checkbox, with multiple boxes checked in the submitted form, when viewing an entry, the pop-up shows for all the checkboxes [object Object]
instead of the value itself.

After exporting entries, all the checkboxed entires are empty in the CSV file.

If there is a solution already I did not find it through my searching.
What might cause this and what are ways to export all the checkbox values selected?

Thanks.

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