Custom constraints validation of multi value paragraphs: highlighting missing field

I am using constraint for the validation my multi value paragraph field.

I can correctly implement the different validation rules but I haven't found out how to highlight only the erroneous field(s).

Here is my violation declaration

      $this->context
       ->buildViolation($constraint->modaliteRequise)
       ->atPath((string) $delta . 'subform.field_modalite.0')
       ->addViolation();

This highlights all fields of all paragraphs.

How can I only highlight the missing field in the affected paragraph?

Thanks Rainer

Ok, I finally found it thanks to https://www.drupal.org/project/paragraphs/issues/2994660#comment-12740155

With following path I can correctly target the field

->atPath((string) $delta . '.subform.field_modalite.widget')

If you want to target a paragraph field from inside another paragraph field you need a path as follows

->atPath((string) '0.subform.TARGET_FIELD.widget.0.subform')