diff --git a/NEWS.mdtext b/NEWS.mdtext
index 5aafb37..c82a54b 100644
--- a/NEWS.mdtext
+++ b/NEWS.mdtext
@@ -4,6 +4,9 @@
 
 ## Bugfixes
 
+- Ensure that IDF does not break UTF-8 encoded strings when
+  shortening them for view rendering (issue 785)
+
 ## Documentation
 
 ## Translations
diff --git a/src/IDF/Views/Source.php b/src/IDF/Views/Source.php
index 81760a0..38913f0 100644
--- a/src/IDF/Views/Source.php
+++ b/src/IDF/Views/Source.php
@@ -506,12 +506,12 @@ function IDF_Views_Source_PrettySizeSimple($size)
 function IDF_Views_Source_ShortenString($string, $length)
 {
     $ellipse = "...";
-    $length = max(strlen($ellipse) + 2, $length);
+    $length = max(mb_strlen($ellipse) + 2, $length);
     $preflen = ceil($length / 10);
 
     if (mb_strlen($string) < $length)
         return $string;
 
-    return substr($string, 0, $preflen).$ellipse.
-           substr($string, -($length - $preflen - mb_strlen($ellipse)));
+    return mb_substr($string, 0, $preflen).$ellipse.
+           mb_substr($string, -($length - $preflen - mb_strlen($ellipse)));
 }