diff --git a/src/Controller/ListUsageController.php b/src/Controller/ListUsageController.php
index 038a7fa..db4fe67 100644
--- a/src/Controller/ListUsageController.php
+++ b/src/Controller/ListUsageController.php
@@ -211,7 +211,7 @@ class ListUsageController extends ControllerBase {
           $used_in_default = FALSE;
           $default_key = 0;
           foreach ($records as $key => $record) {
-            if ($record['source_vid'] == $default_revision_id && $record['source_langcode'] == $default_langcode) {
+            if (($default_revision_id === NULL || $record['source_vid'] == $default_revision_id) && $record['source_langcode'] == $default_langcode) {
               $default_key = $key;
               $used_in_default = TRUE;
               break;