Don't redraw a media-tag everytime the content has changed

www/code/code.css

@@ -53,6 +53,9 @@ body {
   font-family: Calibri, Ubuntu, sans-serif;
   word-wrap: break-word;
 }
+#previewContainer media-tag * {
+  max-width: 100%;
+}
 #preview {
   max-width: 40vw;
   margin: auto;

www/code/code.less

@@ -56,6 +56,9 @@ body {
     box-sizing: border-box;
     font-family: Calibri,Ubuntu,sans-serif;
     word-wrap: break-word;
+    media-tag * {
+        max-width:100%;
+    }
 }
 
 #preview {

www/code/main.js

@@ -9,6 +9,7 @@ define([
     '/common/cryptpad-common.js',
     '/common/cryptget.js',
     '/common/diffMarked.js',
+    '/bower_components/tweetnacl/nacl-fast.min.js', // needed for media-tag
 ], function ($, Crypto, Realtime, TextPatcher, Toolbar, JSONSortify, JsonOT, Cryptpad,
              Cryptget, DiffMd) {
     var Messages = Cryptpad.Messages;