TypeError: b is undefined

Since today i get a typeerror: b is undefined as soon as i go from form mode to code.
It’s like something is changed in the lineItems
how can i solve this ?
pls see screenshot
if i remove the blue box then i see the invoice
i cannot find what b is ?
http://www.pureautomation.be/uploads/invoiceUndefinedType.png
error

The problem could be related to the column widths, try changing back to $invoiceLineItemColumns