Hi,

the 'columns' option of item groups causes line numberings to overlap with each other:

% MWE by Aditya

% https://github.com/adityam/filter/issues/55

% ConTeXt LMTX 2021.09.06 11:47

\starttext
\startlinenumbering
  \input tufte
\stoplinenumbering

\startitemize[columns] \item one \stopitemize
\startitemize[columns] \item one \stopitemize
\startitemize[columns] \item one \stopitemize

\stoptext

Best,

Sylvain