[NTG-context] behavior of \vfill has changed in latest beta

Hi, the behavior of \vfill has changed in the latest beta. In some of my setups, I used code like this to produce vertically centered content: \starttext \null\vfill vertically centered? \vfill\null \stoptext This works with the beta of 2015.11.19 19:13, but no longer with 2015.12.21 12:16. Not sure if intended, side effect, or bug? Thomas