\def\bold:version{bold}
\Configure{mathbf}%
{\bgroup \HCode{<span class="mathvariant-bold">%
<BREAK SIZE="small"/>%
\add:vdescription{font}{bold}<PROS PITCH="-10" >}}%
{\HCode{</PROS><BREAK SIZE="small"/></span>}\egroup }%
\Configure{mathit}%
{\bgroup \HCode{<span
class="mathvariant-\ifx
\bold:version\math@version bold-\fi italic">}}%
{\HCode{</span>}\egroup }%
\Configure{mathrm}%
{\bgroup \HCode{<span class="mathvariant-normal">}}%
{\HCode{</span>}\egroup }%
\Configure{mathsf}%
{\bgroup \HCode{<span
class="mathvariant-\ifx
\bold:version\math@version bold-\fi sans-serif">}}%
{\HCode{</span>}\egroup }%
\Configure{mathtt}%
{\bgroup \HCode{<span class="mathvariant-monospace">}}%
{\HCode{</span>}\egroup }%
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