Use Case: Multiline additional field sizes cannot be modified directly in the UI. These can be modified using Field and Form Rules.
Execution Steps:
1. Create a new 'Multi Line' additional field and copy the "column name" of the additional field created from the additional field listview.
2. Go to Admin > Incident Templates > Select a particular template > Include this additional field in the template > Field and Form Rules > Rule execution - On Create / Edit > Event - "On Form Load" > Actions - Execute Script - Copy Paste the below code snippet and save the script.
var additionalField="WorkOrder_Fields_UDF_CHAR15";
var height=5;
var width="width:150%!important";
jQuery('[name="'+additionalField+'"]').attr('rows',height).attr("style",width);
3. Replace "WorkOrder_Fields_UDF_CHAR15" with the copied "column name" of the additional field.
4. The request additional field will size will be modified in the new request creation form.
Field And Form Rule: