diff --git a/HISTORY.md b/HISTORY.md
index 3823bdd..b2bdd89 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -7,6 +7,7 @@ https://github.com/josdejong/jsoneditor
 
 - Fixed view mode opening links in a new tab instead of current tab
   when Ctrl key is not down. Thanks @LEW21.
+- Fixed #502: code editor not showing a monospaced font some cases.
 
 
 ## 2018-12-28, version 5.13.1
diff --git a/src/js/ace/theme-jsoneditor.js b/src/js/ace/theme-jsoneditor.js
index f890572..1e41b2e 100644
--- a/src/js/ace/theme-jsoneditor.js
+++ b/src/js/ace/theme-jsoneditor.js
@@ -38,7 +38,7 @@ color: #333\
 }\
 \
 .ace-jsoneditor.ace_editor {\
-font-family: droid sans mono, consolas, monospace, courier new, courier, sans-serif;\
+font-family: \"dejavu sans mono\", \"droid sans mono\", consolas, \"lucida console\", monaco, \"courier new\", courier, monospace, sans-serif;\
 line-height: 1.3;\
 background-color: #fff;\
 }\