diff --git a/core/lib/Drupal/Core/Config/ConfigInstaller.php b/core/lib/Drupal/Core/Config/ConfigInstaller.php
index 9fc14b2..ace69e9 100644
--- a/core/lib/Drupal/Core/Config/ConfigInstaller.php
+++ b/core/lib/Drupal/Core/Config/ConfigInstaller.php
@@ -22,11 +22,11 @@ class ConfigInstaller implements ConfigInstallerInterface {
   protected $configFactory;
 
   /**
-   * The active configuration storage.
+   * The active configuration storages, keyed by collection.
    *
-   * @var \Drupal\Core\Config\StorageInterface
+   * @var \Drupal\Core\Config\StorageInterface[]
    */
-  protected $activeStorage;
+  protected $activeStorages;
 
   /**
    * The typed configuration manager.
@@ -79,7 +79,7 @@ class ConfigInstaller implements ConfigInstallerInterface {
    */
   public function __construct(ConfigFactoryInterface $config_factory, StorageInterface $active_storage, TypedConfigManagerInterface $typed_config, ConfigManagerInterface $config_manager, EventDispatcherInterface $event_dispatcher) {
     $this->configFactory = $config_factory;
-    $this->activeStorage = $active_storage;
+    $this->activeStorages[$active_storage->getCollectionName()] = $active_storage;
     $this->typedConfig = $typed_config;
     $this->configManager = $config_manager;
     $this->eventDispatcher = $event_dispatcher;
@@ -191,7 +191,7 @@ protected function createConfiguration($collection, array $config_to_install) {
     }
 
     // Remove configuration that already exists in the active storage.
-    $config_to_install = array_diff($config_to_install, $this->getActiveStorage($collection)->listAll());
+    $config_to_install = array_diff($config_to_install, $this->getActiveStorages($collection)->listAll());
 
     foreach ($config_to_install as $name) {
       // Allow config factory overriders to use a custom configuration object if
@@ -201,7 +201,7 @@ protected function createConfiguration($collection, array $config_to_install) {
         $new_config = $overrider->createConfigObject($name, $collection);
       }
       else {
-        $new_config = new Config($name, $this->getActiveStorage($collection), $this->eventDispatcher, $this->typedConfig);
+        $new_config = new Config($name, $this->getActiveStorages($collection), $this->eventDispatcher, $this->typedConfig);
       }
       if ($data[$name] !== FALSE) {
         $new_config->setData($data[$name]);
@@ -222,7 +222,7 @@ protected function createConfiguration($collection, array $config_to_install) {
           ->getStorage($entity_type);
         // It is possible that secondary writes can occur during configuration
         // creation. Updates of such configuration are allowed.
-        if ($this->getActiveStorage($collection)->exists($name)) {
+        if ($this->getActiveStorages($collection)->exists($name)) {
           $id = $entity_storage->getIDFromConfigName($name, $entity_storage->getEntityType()->getConfigPrefix());
           $entity = $entity_storage->load($id);
           $entity = $entity_storage->updateFromStorageRecord($entity, $new_config->get());
@@ -291,7 +291,7 @@ public function getSourceStorage($collection = StorageInterface::DEFAULT_COLLECT
       // Default to using the ExtensionInstallStorage which searches extension's
       // config directories for default configuration. Only include the profile
       // configuration during Drupal installation.
-      $this->sourceStorage = new ExtensionInstallStorage($this->activeStorage, InstallStorage::CONFIG_INSTALL_DIRECTORY, $collection, drupal_installation_attempted());
+      $this->sourceStorage = new ExtensionInstallStorage($this->getActiveStorages(StorageInterface::DEFAULT_COLLECTION), InstallStorage::CONFIG_INSTALL_DIRECTORY, $collection, drupal_installation_attempted());
     }
     if ($this->sourceStorage->getCollectionName() != $collection) {
       $this->sourceStorage = $this->sourceStorage->createCollection($collection);
@@ -309,11 +309,11 @@ public function getSourceStorage($collection = StorageInterface::DEFAULT_COLLECT
    * @return \Drupal\Core\Config\StorageInterface
    *   The configuration storage that provides the default configuration.
    */
-  protected function getActiveStorage($collection = StorageInterface::DEFAULT_COLLECTION) {
-    if ($this->activeStorage->getCollectionName() != $collection) {
-      $this->activeStorage = $this->activeStorage->createCollection($collection);
+  protected function getActiveStorages($collection = StorageInterface::DEFAULT_COLLECTION) {
+    if (!isset($this->activeStorages[$collection])) {
+      $this->activeStorages[$collection] = reset($this->activeStorages)->createCollection($collection);
     }
-    return $this->activeStorage;
+    return $this->activeStorages[$collection];
   }
 
   /**
@@ -348,7 +348,7 @@ public function findPreExistingConfiguration($type, $name) {
     $enabled_extensions[] = $name;
     foreach ($collection_info->getCollectionNames(TRUE) as $collection) {
       $config_to_install = $this->listDefaultConfigCollection($collection, $type, $name, $enabled_extensions);
-      $active_storage = $this->getActiveStorage($collection);
+      $active_storage = $this->getActiveStorages($collection);
       foreach ($config_to_install as $config_name) {
         if ($active_storage->exists($config_name)) {
           $existing_configuration[$collection][] = $config_name;