If you have 2 date type fields on your form and compare them in a condition builder using date1 is more than 10 days after date2, you get an "onChange script error: TypeError: Cannot read property 'split' of undefined function (){var o=i(m,arguments);return l.apply(n,o)}"

If you change the field types to date/time, you don't get the error. You shouldn't be able to select Date fields if it causes this error.

1) add 2 date fields to the form
2) create a UI policy and build the condition "date1 is more than 10 days after date2"
3) set the dates on your form and observe the error.

change the date fields to date/time fields.