In "Prepare Form" form fields are sometimes auto-generated with names that contain leading space e.g. " _2b". These fields looks innocent in user interaction. But when one want to manipulate them in javascript, they are listed out in getNthFieldName() yet invisible in getField(), thus blocking the automation.

Solution 1: allow leading/trailing space in getField()
Solution 2: trim field names in form field auto-generation

Implement both would be best.