Dear list,

how can I clone \underbar (for the purpose of changing settings for the clone afterwards)?

Just using \definebar to inherit \underbar’s properties does not entirely work, see MWE:

\definebar[myBar][underbar]
\starttext
underbar text mode:	\underbar{$a^b$}	\crlf
underbar math mode:	$\underbar{a^b}$	\crlf
myBar text mode:		\myBar{$a^b$}		\crlf
myBar math mode:		$\myBar{a^b}$
\stoptext

Thanks and best regards,
Florian