diff --git a/src/infrastructure/customfield/standard/PhabricatorStandardCustomField.php b/src/infrastructure/customfield/standard/PhabricatorStandardCustomField.php
--- a/src/infrastructure/customfield/standard/PhabricatorStandardCustomField.php
+++ b/src/infrastructure/customfield/standard/PhabricatorStandardCustomField.php
@@ -389,7 +389,8 @@
     if (is_array($value)) {
       return empty($value);
     }
-    return !strlen($value);
+    $is_empty = phutil_string_cast($value) === '';
+    return $is_empty;
   }
 
   public function getApplicationTransactionTitle(