diff --git a/trac-env/templates/site_head.html b/trac-env/templates/site_head.html
index ffaf0ae..c523c95 100644
--- a/trac-env/templates/site_head.html
+++ b/trac-env/templates/site_head.html
@@ -1,3 +1,4 @@
+<meta name="viewport" content="width=device-width, initial-scale=1" />
 <link rel="stylesheet" href="${href.chrome('site/css/output.css')}" />
 <link rel="stylesheet" href="${href.chrome('site/css/trachacks.css')}" />
 <!--! uncomment for local version of webfont loader if desired. -->