\definetextbackground
  [bg]
  [location=paragraph,
   frame=off,
   background=color]

\setuptyping
  [before={\blank\starttextbackground[bg]},
   after=\stoptextbackground\blank]

\starttext

\startbuffer
  yyy
    xxx
  yyy
\stopbuffer

\bTABLE
  \bTR
    \bTD
      left text
    \eTD
    \bTD
      Some intro:\par
      \typebuffer
      And some next text.\par
    \eTD
  \eTR
\eTABLE

\stoptext