[NTG-context] Bug in \startdocument

Dear devs, It is really convenient to set PDF metadata in \startdocument, however I noticed that there is a bug. The PDF subject is not set using metadata:subject but with metadata:subtitle. This is not a big issue by itself but merely a little confusing. What’s worse is that using metadata:subject throws an error which is completely unexpected at this point. Below you find the error message and a MWE to reproduce. --- ! Undefined control sequence <argument> \c!subject =\documentvariable {metadata:subject} --- \setupinteraction[state=start] \startdocument [ metadata:subject={Subject}, ] Hello World! \stopdocument