Hi,
One way would be to have the following in the prePrint event:
var vName = this.name.toString();
xfa.resolveNode(vName + ".ui.dateTimeEdit.border.edge").presence = "invisible";
/* Check the type of object and change the .ui reference:
Date field = #dateTimeEdit
Dropdown = #choiceList
Checkbox = #checkButton
Text field = #textEdit
Numeric field = #numericEdit
*/
and then a corresponding script in the postPrint setting the presence back to "visible".
The ui properties for other object types are commented out below the script.
You would think that this.border.edge.presence = "invisible"; would work, but it doesn't.
Example here: https://acrobat.com/#d=AwBYYQTNK9WXjSAhp385zQ
Good luck,
Niall