Incorporate the single value delete button from Drupal core 10.2

And here is the patch. This is done against version 4.1.6.

This was way more complicated that I thought. The trick with hiding repeating date instances with #access = FALSE works just fine for the widget display but not when it comes to deleting values.

With a variant of the patch above I got it working so that if you have a repeating date with four instances you can click the Delete button four times to delete the complete "set".

Not very good.