From c8b23195f6ebadeeba83d58fd91f59b1e4ca32b9 Mon Sep 17 00:00:00 2001
From: Lotte Pitcher <github@lottepitcher.co.uk>
Date: Thu, 3 Nov 2016 14:30:38 +0000
Subject: [PATCH] When truncating if the last characters was the first half of
 a two word unicode character, also include the second half to avoid YSOD

---
 src/Umbraco.Web/HtmlStringUtilities.cs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/Umbraco.Web/HtmlStringUtilities.cs b/src/Umbraco.Web/HtmlStringUtilities.cs
index 5ba1d17f4e..24a643b5b0 100644
--- a/src/Umbraco.Web/HtmlStringUtilities.cs
+++ b/src/Umbraco.Web/HtmlStringUtilities.cs
@@ -211,6 +211,13 @@ namespace Umbraco.Web
 
                                     if (!lengthReached && currentTextLength >= length)
                                     {
+                                        // if the last character added was the first of a two character unicode pair, add the second character
+                                        if (Char.IsHighSurrogate((char)ic))
+                                        {
+                                            var lowSurrogate = tr.Read();
+                                            outputtw.Write((char)lowSurrogate);
+                                        }
+
                                         // Reached truncate limit.
                                         if (addElipsis)
                                         {