Hi again,
By a coincident, I found out how to get rid of this bug. I unactivated the plu in: Woo Commerce Product add-ons. Might help somebody else.
I have been waiting since february for this bug to be resolved. When choosing “print invoice, delivery note or receipt”, f ex an invoice is shown, correcly at the top but with the text “an critical error has occurred” further down
Please fix this bug
