diff --git a/web_src/css/markup/codepreview.css b/web_src/css/markup/codepreview.css
index 921954499..c9d19f5cc 100644
--- a/web_src/css/markup/codepreview.css
+++ b/web_src/css/markup/codepreview.css
@@ -12,7 +12,7 @@
 
 .markup .code-preview-container table {
   width: 100%;
-  max-height: 100px;
+  max-height: 240px; /* 12 lines at 20px per line */
   overflow-y: auto;
   margin: 0; /* override ".markup table {margin}" */
 }