[NTG-context] Bug in lmtx with \Bbb

Hi Hans, It seems that there is a bug in the handling of Blackboard Bold, in the latest lmtx (version 2019.08.02 19:40). The following gives the attached PDF file. However the same file typesets correctly in the latest mkiv beta. Thanks for your attention: OK \starttext The set of integers is denoted ${\Bbb N}$. \stoptext