diff --git a/core/modules/layout_builder/src/Form/LayoutBuilderEntityViewDisplayForm.php b/core/modules/layout_builder/src/Form/LayoutBuilderEntityViewDisplayForm.php
index 955027a5df..5b299ecaa1 100644
--- a/core/modules/layout_builder/src/Form/LayoutBuilderEntityViewDisplayForm.php
+++ b/core/modules/layout_builder/src/Form/LayoutBuilderEntityViewDisplayForm.php
@@ -113,7 +113,8 @@ public function form(array $form, FormStateInterface $form_state) {
         unset($form['#entity_builders']['layout_builder']);
       }
     }
-    elseif ($this->entity->getMode() === 'default') {
+    // For non-canonical modes, the existing value should be preserved.
+    else {
       $form['layout']['allow_custom'] = [
         '#type' => 'value',
         '#value' => $this->entity->isOverridable(),