diff --git a/app/views/topics/plain.html.erb b/app/views/topics/plain.html.erb
index 7c852a3b691..8facc6a9563 100644
--- a/app/views/topics/plain.html.erb
+++ b/app/views/topics/plain.html.erb
@@ -6,6 +6,7 @@
   <%= crawlable_meta_data(title: @topic_view.title,
                           description: @topic_view.summary,
                           image: @topic_view.image_url) %>
+  <meta name="viewport" content="width=device-width, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes">
 </head>
 <body>
 <% @topic_view.posts.each do |post| %>
