diff --git a/radicale/web/internal_data/fn.js b/radicale/web/internal_data/fn.js
index 935a574..668df03 100644
--- a/radicale/web/internal_data/fn.js
+++ b/radicale/web/internal_data/fn.js
@@ -44,11 +44,11 @@ const COLOR_RE = new RegExp("^(#[0-9A-Fa-f]{6})(?:[0-9A-Fa-f]{2})?$");
  */
 function escape_xml(s) {
     return (s
-            .replace("&", "&")
-            .replace('"', """)
-            .replace("'", "'")
-            .replace("<", "&lt;")
-            .replace(">", "&gt;"));
+            .replace(/&/g, "&amp;")
+            .replace(/"/g, "&quot;")
+            .replace(/'/g, "&apos;")
+            .replace(/</g, "&lt;")
+            .replace(/>/g, "&gt;"));
 }
 
 /**