Steps to reproduce the issue

1. Create a component with a repeatable calendar field or install the attached component. com_repeteable-1.0.0.zip
2. Add two or more calendar fields
3. Click save and Close
4. Edit the field again
5. Add another calendar field by clicking the top green plus button
6. Attempt to select a date in the newly added field

Expected result

The date selector shows

Actual result

Nothing happens. The date selector does not load

System information (as much as possible)

Joomla 3.8.3
Example component created with Component Creator

Additional comments

Please note that clicking on the top green [+] button when first adding fields works. It is only when editing the item that the problem occurs.

Please also note that clicking on the green [+] buttons next to existing fields does work.