The following may serve as a guide to others in formatting long quotations or extracts:
<!-- wiki visitors will probably not find this code at this place - where could it go? -->
<texcode>
%%%% In body text
\defineblank[extractdistance][3pt]
\definestartstop[extract][
before={\blank[extractdistance] %[extractdistance,force] causes spurious overfull \hbox warnings
\setupnarrower[left=1.5pc,right=1.5pc]
\startnarrower[left,right]
\noindent},
after={\stopnarrower
\blank[extractdistance]
\indenting[yes]}]
%%%% In footnotes
\defineblank[footenoteextractdistance][2.7pt]
\definestartstop[fnextract][
before={\blank[footenoteextractdistance]
\setupnarrower[left=1.5pc,right=1.5pc]
\startnarrower[left,right]
\noindent},
after={\stopnarrower
\blank[footenoteextractdistance]
\indenting[yes]}]
</texcode>