I meant auto... oops

_sass/code.scss

@@ -48,7 +48,7 @@ div.highlighter-rouge {
   padding: $sp-3;
   margin-top: 0;
   margin-bottom: $sp-3;
-  overflow-x: hidden;
+  overflow-x: auto;
   background-color: $code-background-color;
   border-radius: $border-radius;
   box-shadow: none;