Hello,

with \setupalign[flushleft] non-breakable space has different width than regular space. With pure \rightskip0pt plus 1fill all spaces are equal. Is this wanted behaviour or do I miss additional settings?

\showmakeup[glue]
\startTEXpage[width=80mm,offset=5mm]
\rightskip0pt plus 1fill
woo woo woo woo woo woo woo woo woo woo
\blank
\setupalign[flushleft]
woo woo woo woo woo woo woo woo woo woo
\stopTEXpage

MWE also in the attachment to preserve nbsp.

Regards,

Jano