diff --git a/token.tokens.inc b/token.tokens.inc
index 564b22e..8acbd4a 100644
--- a/token.tokens.inc
+++ b/token.tokens.inc
@@ -1428,6 +1428,7 @@ function field_tokens($type, $tokens, array $data = array(), array $options = ar
         if (count($parts) > 1) {
           $delta = $parts[0];
           $property_name = $parts[1];
+          // Pre-filter the tokens to select those with the correct delta.
           $filtered_tokens = \Drupal::token()->findWithPrefix($tokens, $delta);
           // Remove the delta to unify between having and not having one.
           array_shift($parts);