diff --git a/includes/bootstrap.inc b/includes/bootstrap.inc
index 9d3e44cd0c1f..2a0f7e52de47 100644
--- a/includes/bootstrap.inc
+++ b/includes/bootstrap.inc
@@ -707,9 +707,15 @@ function arg($index) {
   }
 }
 
+/**
+ * Encode special characters in a plain-text string for display as HTML.
+ */
+function check_plain($text) {
+  return htmlspecialchars($text, ENT_QUOTES);
+}
+
 /**
  * Prepare a URL for use in an HTML attribute. Strips harmful protocols.
- *
  */
 function check_url($uri) {
   $uri = htmlspecialchars($uri, ENT_QUOTES);