Changes to code components in global regions is not loaded until published

So this does not happen when the auto-saved code component is in a content entity's XB field, and only if it is in a PageRegion?

If so, this would be a missed edge case in 📌 Code Components should render with their auto-saved state(if any) when rendered in the XB UI Active .

Or are you referring to the PageRegion itself being auto-saved?

So this does not happen when the auto-saved code component is in a content entity's XB field, and only if it is in a PageRegion?

Yes, exactly. This is what I tried to describe in the steps to reproduce.

25-min deep dive suggests this is because 📌 Code Components should render with their auto-saved state(if any) when rendered in the XB UI Active only modified \Drupal\experience_builder\Controller\ApiLayoutController::buildPreviewRenderable() to do:

$renderable = $item->toRenderable(TRUE);

which results in a JsComponent::renderComponent(isPreview: TRUE) call, rendering the auto-save (draft).

But the page regions are not rendered in ::buildPreviewRenderable(), but in \Drupal\experience_builder\Plugin\DisplayVariant\XbPageVariant::build(), where there's still this:

      $fiber = new \Fiber(fn() => $component_tree->toRenderable());

(note the absence of isPreview: TRUE)

It'll be up to \Drupal\experience_builder\EventSubscriber\PreviewEnvelopeViewSubscriber::onViewPreviewEnvelope() to pass that information to XbPageVariant somehow.

AFAICT the only feasible approach is to rely on this bit in HtmlRenderer:

      // Instantiate the page display, and give it the main content.
      $page_display = $this->displayVariantManager->createInstance($variant_id, $variant_configuration);
      if (!$page_display instanceof PageVariantInterface) {
        throw new \LogicException('Cannot render the main content for this page because the provided display variant does not implement PageVariantInterface.');
      }
      $page_display
        ->setMainContent($main_content)
        ->setTitle($title)
        ->addCacheableDependency($event);
      // Some display variants need to be passed an array of contexts with
      // values because they can't get all their contexts globally. For example,
      // in Page Manager, you can create a Page which has a specific static
      // context (e.g. a context that refers to the Node with nid 6), if any
      // such contexts were added to the $event, pass them to the $page_display.
      if ($page_display instanceof ContextAwareVariantInterface) {
        $page_display->setContexts($event->getContexts());
      }

IOW: update XbPageVariant to implement ContextAwareVariantInterface. Then do something like \Drupal\display_variant_test\EventSubscriber\TestPageDisplayVariantSubscriber::onSelectPageDisplayVariant() to provide a yet-to-be-created "XB preview" context, which can then be respected by XbPageVariant, and which would result in $page_display->setContrexts(['xb_preview' => TRUE]);.

The only alternative I see: add a #xb_preview => TRUE key-value pair to the "main content", which then is detected by XbPageVariant.

⚠️ AFAICT this also affects the component preview upon hovering the list of available components:

diff --git a/src/Plugin/ExperienceBuilder/ComponentSource/BlockComponent.php b/src/Plugin/ExperienceBuilder/ComponentSource/BlockComponent.php
index 4fbac989c..adb573f8d 100644
--- a/src/Plugin/ExperienceBuilder/ComponentSource/BlockComponent.php
+++ b/src/Plugin/ExperienceBuilder/ComponentSource/BlockComponent.php
@@ -302,7 +302,7 @@ final class BlockComponent extends ComponentSourceBase implements ContainerFacto
       return ['build' => []];
     }
 
-    return ['build' => $this->renderComponent([], $component->uuid())];
+    return ['build' => $this->renderComponent([], $component->uuid(), TRUE)];
   }
 
   /**
diff --git a/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php b/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php
index c55528b5b..39653166a 100644
--- a/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php
+++ b/src/Plugin/ExperienceBuilder/ComponentSource/GeneratedFieldExplicitInputUxComponentSourceBase.php
@@ -603,7 +603,7 @@ abstract class GeneratedFieldExplicitInputUxComponentSourceBase extends Componen
 
     return [
       'source' => (string) $this->getSourceLabel(),
-      'build' => $this->renderComponent([self::EXPLICIT_INPUT_NAME => $default_props_for_default_markup], $component->uuid()),
+      'build' => $this->renderComponent([self::EXPLICIT_INPUT_NAME => $default_props_for_default_markup], $component->uuid(), TRUE),
       // Additional data only needed for SDCs.
       // @todo UI does not use any other metadata - should `slots` move to top level?
       'metadata' => ['slots' => $this->getSlotDefinitions()],

Extracting #5 into a separate issue, because as @f.mazeikis and @longwave pointed out: there's cache invalidation challenges there. So extracted A) preview-on-hover into 🐛 Changes to code components are not visible in preview-on-hover-component-list until published Active .