diff --git a/mozilla/webtools/bugzilla/template/en/default/attachment/diff-header.html.tmpl b/mozilla/webtools/bugzilla/template/en/default/attachment/diff-header.html.tmpl
index 29fe14a7a48..c6b14d9a062 100644
--- a/mozilla/webtools/bugzilla/template/en/default/attachment/diff-header.html.tmpl
+++ b/mozilla/webtools/bugzilla/template/en/default/attachment/diff-header.html.tmpl
@@ -66,7 +66,9 @@ table.file_table {
 
 tbody.file pre {
   display: inline;
-  white-space: -moz-pre-wrap;
+  white-space: pre-wrap; /* CSS 3 & CSS 2.1 */
+  white-space: -moz-pre-wrap; /* Gecko < 1.9.1 */
+  white-space: -o-pre-wrap; /* Opera 7 */
   font-size: 0.9em;
 }