Forms that you create with Form Builder can use formulas. Most formulas are currently written “by hand” (not unlike Excel formulas). This means that they can, unfortunately, contain some errors. Some are caught by Form Builder when you write them, but some can only appear when you run the form.
In the past, it was hard to figure out such errors. But Form Builder, since version 2023.1, features a Formulas console which is available when you test a form using the “Test Form” function.
The console lists every individual error with details about each. If an error occurs while testing the form, you can quickly go back to Form Builder by closing the Form Preview dialog and modifying the problematic formula.
See also the documentation.
We hope you will enjoy this feature of Orbeon Forms 2023.1!