diff --git a/core/core.services.yml b/core/core.services.yml
index 47ee363..afd35a0 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -1479,6 +1479,22 @@ services:
     arguments: ['@controller_resolver', '@renderer']
     tags:
       - { name: event_subscriber }
+  # Render strategies for rendering placeholders.
+  render_strategy_html.subscriber:
+    class: Drupal\Core\EventSubscriber\HtmlRenderStrategySubscriber
+    tags:
+      - { name: event_subscriber }
+    arguments: ['@render_strategy_manager']
+  render_strategy_manager:
+    class: Drupal\Core\Render\Strategy\RenderStrategyManager
+    arguments: ['@renderer']
+    tags:
+      - { name: service_collector, tag: render_strategy, call: addRenderStrategy }
+    lazy: true
+  render_strategy.single_flush:
+    class: Drupal\Core\Render\Strategy\SingleFlushRenderStrategy
+    tags:
+      - { name: render_strategy, priority: -1000 }
   email.validator:
     class: Egulias\EmailValidator\EmailValidator
 
diff --git a/core/lib/Drupal/Core/EventSubscriber/HtmlRenderStrategySubscriber.php b/core/lib/Drupal/Core/EventSubscriber/HtmlRenderStrategySubscriber.php
new file mode 100644
index 0000000..d40f451
--- /dev/null
+++ b/core/lib/Drupal/Core/EventSubscriber/HtmlRenderStrategySubscriber.php
@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\EventSubscriber\HtmlRenderStrategySubscriber.
+ */
+
+namespace Drupal\Core\EventSubscriber;
+
+use Drupal\Core\Render\HtmlResponse;
+use Drupal\Core\Render\Strategy\RenderStrategyManagerInterface;
+use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
+use Symfony\Component\HttpKernel\KernelEvents;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+/**
+ * Response subscriber to handle render strategies for HTML responses.
+ */
+class HtmlRenderStrategySubscriber implements EventSubscriberInterface {
+
+  /**
+   * The render strategy manager service.
+   *
+   * @var \Drupal\Core\Render\Strategy\RenderStrategyManager
+   */
+  protected $renderStrategyManager;
+
+  /**
+   * Constructs a HtmlRenderStrategySubscriber object.
+   *
+   * @param \Drupal\Core\Render\Strategy\RenderStrategyManagerInterface $render_strategy_manager
+   *   The render strategy manager service.
+   */
+  public function __construct(RenderStrategyManagerInterface $render_strategy_manager) {
+    $this->renderStrategyManager = $render_strategy_manager;
+  }
+
+  /**
+   * Processes attachments for HtmlResponse responses.
+   *
+   * @param \Symfony\Component\HttpKernel\Event\FilterResponseEvent $event
+   *   The event to process.
+   */
+  public function onRespond(FilterResponseEvent $event) {
+    if (!$event->isMasterRequest()) {
+      return;
+    }
+
+    $response = $event->getResponse();
+    if (!$response instanceof HtmlResponse) {
+      return;
+    }
+
+    $attachments = $response->getAttachments();
+    if (empty($attachments['placeholders'])) {
+      return;
+    }
+
+    $attachments['placeholders'] = $this->renderStrategyManager->processPlaceholders($attachments['placeholders']);
+
+    $response->setAttachments($attachments);
+    $event->setResponse($response);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function getSubscribedEvents() {
+    // Run shortly before HtmlResponseSubscriber.
+    $events[KernelEvents::RESPONSE][] = ['onRespond', 5];
+    return $events;
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Render/HtmlResponse.php b/core/lib/Drupal/Core/Render/HtmlResponse.php
index c5339d6..7f9ab4d 100644
--- a/core/lib/Drupal/Core/Render/HtmlResponse.php
+++ b/core/lib/Drupal/Core/Render/HtmlResponse.php
@@ -42,6 +42,6 @@ public function setContent($content) {
       $content = $content['#markup'];
     }
 
-    parent::setContent($content);
+    return parent::setContent($content);
   }
 }
diff --git a/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php b/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
index 50ff584..67f3507 100644
--- a/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
+++ b/core/lib/Drupal/Core/Render/HtmlResponseAttachmentsProcessor.php
@@ -99,6 +99,12 @@ public function processAttachments(AttachmentsInterface $response) {
       throw new \InvalidArgumentException('\Drupal\Core\Render\HtmlResponse instance expected.');
     }
 
+    // First, render the actual placeholders; this may cause additional
+    // attachments to be added to the response, which the attachment
+    // placeholders rendered by renderHtmlResponseAttachmentPlaceholders() will
+    // need to include.
+    $this->renderPlaceholders($response);
+
     $attached = $response->getAttachments();
 
     // Get the placeholders from attached and then remove them.
@@ -118,7 +124,7 @@ public function processAttachments(AttachmentsInterface $response) {
     }
 
     // Now replace the placeholders in the response content with the real data.
-    $this->renderPlaceholders($response, $placeholders, $variables);
+    $this->renderHtmlResponseAttachmentPlaceholders($response, $placeholders, $variables);
 
     // Finally set the headers on the response.
     $headers = drupal_get_http_header();
@@ -127,6 +133,31 @@ public function processAttachments(AttachmentsInterface $response) {
     return $response;
   }
 
+ /**
+   * Renders placeholders (#attached[placeholders]).
+   *
+   * @param \Drupal\Core\Render\HtmlResponse $response
+   *   The HTML response whose placeholders to replace.
+   *
+   * @see \Drupal\Core\Render\Renderer::replacePlaceholders()
+   * @see \Drupal\Core\Render\Renderer::renderPlaceholder()
+   */
+  protected function renderPlaceholders(HtmlResponse $response) {
+    // Render the placeholders in the HTML Response object.
+    $build = [
+      '#markup' => SafeString::create($response->getContent()),
+      '#attached' => $response->getAttachments(),
+    ];
+    $this->renderer->renderRoot($build);
+
+    // Update the Response object now that the placeholders have been rendered.
+    $placeholders_bubbleable_metadata = BubbleableMetadata::createFromRenderArray($build);
+    $response
+      ->setContent($build['#markup'])
+      ->addCacheableDependency($placeholders_bubbleable_metadata)
+      ->setAttachments($placeholders_bubbleable_metadata->getAttachments());
+  }
+
   /**
    * Processes asset libraries into render arrays.
    *
@@ -186,7 +217,7 @@ protected function processAssetLibraries(array $attached, array $placeholders) {
    *   The variables to render and replace, keyed by type with renderable
    *   arrays as values.
    */
-  protected function renderPlaceholders(HtmlResponse $response, array $placeholders, array $variables) {
+  protected function renderHtmlResponseAttachmentPlaceholders(HtmlResponse $response, array $placeholders, array $variables) {
     $content = $response->getContent();
     foreach ($placeholders as $type => $placeholder) {
       if (isset($variables[$type])) {
diff --git a/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php b/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
index 7e06aab..b701344 100644
--- a/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
+++ b/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
@@ -11,6 +11,7 @@
 use Drupal\Core\Controller\TitleResolverInterface;
 use Drupal\Core\Display\PageVariantInterface;
 use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Render\BubbleableMetadata;
 use Drupal\Core\Render\HtmlResponse;
 use Drupal\Core\Render\PageDisplayVariantSelectionEvent;
 use Drupal\Core\Render\RenderCacheInterface;
@@ -125,9 +126,23 @@ public function renderResponse(array $main_content, Request $request, RouteMatch
     // page.html.twig, hence add them here, just before rendering html.html.twig.
     $this->buildPageTopAndBottom($html);
 
-    // @todo https://www.drupal.org/node/2495001 Make renderRoot return a
-    //       cacheable render array directly.
-    $this->renderer->renderRoot($html);
+    // Render, but don't replace placeholders yet, because that happens later in
+    // the render pipeline.
+    // @see \Drupal\Core\Render\HtmlResponseAttachmentsProcessor.
+    $render_context = new RenderContext();
+    $this->renderer->executeInRenderContext($render_context, function() use (&$html) {
+      // RendererInterface::render() renders the $html render array, it updates
+      // $html by reference. We don't care about the return value (which is just
+      // $html['#markup']), but about the resulting render array.
+      // @todo Simplify this when https://www.drupal.org/node/2495001 lands.
+      $this->renderer->render($html);
+    });
+    if (!$render_context->isEmpty()) {
+      $bubbleable_metadata = $render_context->pop();
+      BubbleableMetadata::createFromRenderArray($html)
+        ->merge($bubbleable_metadata)
+        ->applyTo($html);
+    }
     $content = $this->renderCache->getCacheableRenderArray($html);
 
     // Also associate the "rendered" cache tag. This allows us to invalidate the
diff --git a/core/lib/Drupal/Core/Render/Renderer.php b/core/lib/Drupal/Core/Render/Renderer.php
index cbd9ca8..7e3d428 100644
--- a/core/lib/Drupal/Core/Render/Renderer.php
+++ b/core/lib/Drupal/Core/Render/Renderer.php
@@ -163,10 +163,8 @@ public function renderPlain(&$elements) {
    *   The updated $elements.
    *
    * @see ::replacePlaceholders()
-   *
-   * @todo Make public as part of https://www.drupal.org/node/2469431
    */
-  protected function renderPlaceholder($placeholder, array $elements) {
+  public function renderPlaceholder($placeholder, array $elements) {
     // Get the render array for the given placeholder
     $placeholder_elements = $elements['#attached']['placeholders'][$placeholder];
 
@@ -272,12 +270,6 @@ protected function doRender(&$elements, $is_root_call = FALSE) {
       $cached_element = $this->renderCache->get($elements);
       if ($cached_element !== FALSE) {
         $elements = $cached_element;
-        // Only when we're in a root (non-recursive) Renderer::render() call,
-        // placeholders must be processed, to prevent breaking the render cache
-        // in case of nested elements with #cache set.
-        if ($is_root_call) {
-          $this->replacePlaceholders($elements);
-        }
         // Mark the element markup as safe if is it a string.
         if (is_string($elements['#markup'])) {
           $elements['#markup'] = SafeString::create($elements['#markup']);
@@ -288,6 +280,14 @@ protected function doRender(&$elements, $is_root_call = FALSE) {
         // Render cache hit, so rendering is finished, all necessary info
         // collected!
         $context->bubble();
+
+        // Only when we're in a root (non-recursive) Renderer::render() call,
+        // placeholders must be processed, to prevent breaking the render cache
+        // in case of nested elements with #cache set.
+        if ($is_root_call) {
+          $this->replacePlaceholders($elements);
+        }
+
         return $elements['#markup'];
       }
     }
@@ -525,6 +525,16 @@ protected function doRender(&$elements, $is_root_call = FALSE) {
       $this->renderCache->set($elements, $pre_bubbling_elements);
     }
 
+    if ($is_root_call) {
+      // @todo remove as part of https://www.drupal.org/node/2511330.
+      if ($context->count() !== 1) {
+        throw new \LogicException('A stray drupal_render() invocation with $is_root_call = TRUE is causing bubbling of attached assets to break.');
+      }
+    }
+
+    // Rendering is finished, all necessary info collected!
+    $context->bubble();
+
     // Only when we're in a root (non-recursive) Renderer::render() call,
     // placeholders must be processed, to prevent breaking the render cache in
     // case of nested elements with #cache set.
@@ -536,15 +546,8 @@ protected function doRender(&$elements, $is_root_call = FALSE) {
     // that is handled earlier in Renderer::render().
     if ($is_root_call) {
       $this->replacePlaceholders($elements);
-      // @todo remove as part of https://www.drupal.org/node/2511330.
-      if ($context->count() !== 1) {
-        throw new \LogicException('A stray drupal_render() invocation with $is_root_call = TRUE is causing bubbling of attached assets to break.');
-      }
     }
 
-    // Rendering is finished, all necessary info collected!
-    $context->bubble();
-
     $elements['#printed'] = TRUE;
     return SafeString::create($elements['#markup']);
   }
diff --git a/core/lib/Drupal/Core/Render/Strategy/RenderStrategyInterface.php b/core/lib/Drupal/Core/Render/Strategy/RenderStrategyInterface.php
new file mode 100644
index 0000000..e6abbd5
--- /dev/null
+++ b/core/lib/Drupal/Core/Render/Strategy/RenderStrategyInterface.php
@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Render\Strategy\RenderStrategyInterface.
+ */
+
+namespace Drupal\Core\Render\Strategy;
+
+/**
+ * Provides an interface for defining a render strategy service.
+ */
+interface RenderStrategyInterface {
+
+  /**
+   * Processes placeholders to render them with different strategies.
+   *
+   * @param array $placeholders
+   *   The placeholders to process keyed by $placeholder_id with the render
+   *   cache array as value.
+   *
+   * @return array $placeholders
+   *   The new values for the placeholders, keyed by $placeholder_id => $render_array.
+   */
+  public function processPlaceholders(array $placeholders);
+
+}
diff --git a/core/lib/Drupal/Core/Render/Strategy/RenderStrategyManager.php b/core/lib/Drupal/Core/Render/Strategy/RenderStrategyManager.php
new file mode 100644
index 0000000..2a18a72
--- /dev/null
+++ b/core/lib/Drupal/Core/Render/Strategy/RenderStrategyManager.php
@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Render\Strategy\RenderStrategyManager.
+ */
+
+namespace Drupal\Core\Render\Strategy;
+
+use Drupal\Core\Render\RendererInterface;
+
+/**
+ * Provides a class which allows to render placeholders.
+ */
+class RenderStrategyManager implements RenderStrategyManagerInterface {
+
+  /**
+   * The renderer.
+   *
+   * @var \Drupal\Core\Render\RendererInterface
+   */
+  protected $renderer;
+
+  /**
+   * The RenderStrategy services.
+   *
+   * @var Drupal\Core\Render\Strategy\RenderStrategyInterface[]
+   */
+  protected $renderStrategies;
+
+  /**
+   * Constructs a new RenderStrategyManager class.
+   *
+   * @param \Drupal\Core\Render\RendererInterface
+   *   The renderer.
+   */
+  public function __construct(RendererInterface $renderer) {
+    $this->renderer = $renderer;
+  }
+
+  /**
+   * Adds a render strategy to process.
+   *
+   * @param RenderStrategyInterface $strategy
+   *   The strategy to add to the render strategies.
+   */
+  public function addRenderStrategy(RenderStrategyInterface $strategy) {
+    $this->renderStrategies[] = $strategy;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processPlaceholders(array $placeholders) {
+    if (empty($placeholders)) {
+      return [];
+    }
+
+    $new_placeholders = [];
+
+    // Give each render strategy a chance to replace all not-yet replaced
+    // placeholders.
+    foreach ($this->renderStrategies as $strategy) {
+      $processed_placeholders = $strategy->processPlaceholders($placeholders);
+      $placeholders = array_diff_key($placeholders, $processed_placeholders);
+      $new_placeholders += $processed_placeholders;
+
+      if (empty($placeholders)) {
+        break;
+      }
+    }
+
+    return $new_placeholders;
+  }
+
+}
diff --git a/core/lib/Drupal/Core/Render/Strategy/RenderStrategyManagerInterface.php b/core/lib/Drupal/Core/Render/Strategy/RenderStrategyManagerInterface.php
new file mode 100644
index 0000000..0120f50
--- /dev/null
+++ b/core/lib/Drupal/Core/Render/Strategy/RenderStrategyManagerInterface.php
@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Render\Strategy\RenderStrategyManagerInterface.
+ */
+
+namespace Drupal\Core\Render\Strategy;
+
+/**
+ * Provides an interface which allows to process placeholders.
+ */
+interface RenderStrategyManagerInterface {
+
+  /**
+   * Processes placeholders with different strategies.
+   *
+   * @param array $placeholders
+   *   The placeholders to process.
+   *
+   * @return array
+   *   The processed placeholders.
+   */
+  public function processPlaceholders(array $placeholders);
+
+}
diff --git a/core/lib/Drupal/Core/Render/Strategy/SingleFlushRenderStrategy.php b/core/lib/Drupal/Core/Render/Strategy/SingleFlushRenderStrategy.php
new file mode 100644
index 0000000..7bed91e
--- /dev/null
+++ b/core/lib/Drupal/Core/Render/Strategy/SingleFlushRenderStrategy.php
@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Render\Strategy\SingleFlushRenderStrategy
+ */
+
+namespace Drupal\Core\Render\Strategy;
+
+/**
+ * Defines the 'single_flush' render strategy.
+ *
+ * This is the last strategy that always replaces all remaining placeholders.
+ */
+class SingleFlushRenderStrategy implements RenderStrategyInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function processPlaceholders(array $placeholders) {
+    // Return all placeholders as is; they should be rendered directly.
+    return $placeholders;
+  }
+}