[NTG-context] Underful with \startalignment[flushright]

Dear list, Could not find any hint on this list on this (minor) problem. When compiling the following simple MWE : \starttext \startalignment[flushright] Foo. \stopalignment \stoptext I get an underful hbox message : Underfull \hbox (badness 10000) in paragraph at lines 4--5 []\3>modern-designsize-12pt-rm-tf-0--0 Foo. Is there a simple way to avoid the underful message (other than adding a \hfil before the text) ? \starttext \startalignment[flushright] \hfil Foo. \stopalignment \stoptext Many thanks Best regards Joseph Canedo