diff --git a/book/tex4ebook.cfg b/book/tex4ebook.cfg
index 35066f6..dffea80 100644
--- a/book/tex4ebook.cfg
+++ b/book/tex4ebook.cfg
@@ -19,18 +19,4 @@
     font-family: 'Open Sans';
   }
 </style>}}
-
-% Deal with chemical equations in a single svg
-\ExplSyntaxOn
-\def\standaloneenv#1{}
-\pend:def\schemestart{\Picture+{}}
-\append:def\CF_schemestop{\EndPicture}
-\ExplSyntaxOff
-\makeatletter
-\def\texfourht@tikz@begin{
-  \protect\csname nested:math\endcsname% support display math
-  \Picture+[\csname a:Picture-alt\endcsname]{}%
-}
-\makeatother
-
 \EndPreamble
diff --git a/book/website.cfg b/book/website.cfg
index b87e680..f236b6e 100644
--- a/book/website.cfg
+++ b/book/website.cfg
@@ -47,17 +47,5 @@
 }
 \ConfigureToc{loc}{\HCode{<span class="lofToc">}}{\ }{}{\HCode{</span><br />}}
 
-\ExplSyntaxOn
-\def\standaloneenv#1{}
-\pend:def\schemestart{\Picture+{}}
-\append:def\CF_schemestop{\EndPicture}
-\ExplSyntaxOff
-\makeatletter
-\def\texfourht@tikz@begin{
-  \protect\csname nested:math\endcsname% support display math
-  \Picture+[\csname a:Picture-alt\endcsname]{}%
-}
-\makeatother
-
 \begin{document}
 \EndPreamble