I would like the right edges line up perfectly.
\starttext
\startframedtext[width=local]\input tufte\stopframedtext
Before list.
\startitemize
\startitem item one\stopitem
\startitem item two\startframedtext[width=local]\input tufte\stopframedtext\stopitem
\startitem item three\stopitem
\stopitemize
After list.
\startframedtext[width=local]\input tufte\stopframedtext
\stoptext