\Configure{leqalignno}
{\HCode{<mtable class="leqalignno">}}
{\HCode{</mtable>}}
{\HCode{<mtr\Hnewline class="leqalignno">}}
{\HCode{</mtr>}}
{\HCode{<mtd \Hnewline class="leqalignno-\HCol">}}
{\HCode{</mtd>}}
\def\:leqalignno:{\Configure{noalign}
{\HCode{<mtr><mtd class="noalign" colspan="2">}}%
{\HCode{</mtd></mtr>}}}
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