whiteSpace=collapse facet with textarea - value is trimmed and contiguous whitespaces are collapsed, all whitespaces become spaces. Good for names, titles etc..

Collapse *Required string field with ctrl.emptyisnull=true and whiteSpace=collapse facet, whitespace is collapsed, whitespace only values are converted to the {absent} (null) value because of emptyisnull=false.

Collapse Empty Is Null False(Opzionale)Required string field with ctrl.emptyisnull=false and whiteSpace=collapse facet, whitespace is collapsed, whitespace only values are converted to the empty string because of whitespace facet and emptyisnull=false. Also form.empty=true is used to disable HTML5 @required as it would not let submit an empty string.