The \begin#1 command has been expanded to call ‘\csname on#1:list\endcsname’ before calling ‘\csname #1\endcsname’, if \this:listConfigure is empty.
<..latex ltlists..>
\long\def\ConfigureList#1#2#3#4#5{\expandafter
\def\csname on#1:list\endcsname{\def\this:listConfigure{%
\def\:DLL{#2}\def\:DT{#4}\def\:DD{#5}\def\end:DL{#3}%
\tmp:cnt=0 \def\:temp{#2#3#4#5}%
\g:let\:DLL{#1}\g:let\:DT{#1}\g:let\:DD{#1}\g:let\end:DL{#1}%
}}}
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<..html lists..>
\let\:DL:=\empty
\let\:OL:=\empty
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