diff --git a/core/lib/Drupal/Core/Extension/ThemeHandlerInterface.php b/core/lib/Drupal/Core/Extension/ThemeHandlerInterface.php
index 03afd2b..5f3a6cf 100644
--- a/core/lib/Drupal/Core/Extension/ThemeHandlerInterface.php
+++ b/core/lib/Drupal/Core/Extension/ThemeHandlerInterface.php
@@ -8,45 +8,11 @@
 namespace Drupal\Core\Extension;
 
 /**
- * Manages the list of available themes as well as install/uninstall them.
+ * Manages the list of available themes.
  */
 interface ThemeHandlerInterface {
 
   /**
-   * Installs a given list of themes.
-   *
-   * @param array $theme_list
-   *   An array of theme names.
-   * @param bool $install_dependencies
-   *   (optional) If TRUE, dependencies will automatically be installed in the
-   *   correct order. This incurs a significant performance cost, so use FALSE
-   *   if you know $theme_list is already complete and in the correct order.
-   *
-   * @return bool
-   *   Whether any of the given themes have been installed.
-   *
-   * @throws \Drupal\Core\Extension\ExtensionNameLengthException
-   *   Thrown when the theme name is to long
-   */
-  public function install(array $theme_list, $install_dependencies = TRUE);
-
-  /**
-   * Uninstalls a given list of themes.
-   *
-   * Uninstalling a theme removes all related configuration (like blocks) and
-   * invokes the 'themes_uninstalled' hook.
-   *
-   * @param array $theme_list
-   *   The themes to uninstall.
-   *
-   * @throws \InvalidArgumentException
-   *   Thrown when you uninstall an not installed theme.
-   *
-   * @see hook_themes_uninstalled()
-   */
-  public function uninstall(array $theme_list);
-
-  /**
    * Returns a list of currently installed themes.
    *
    * @return \Drupal\Core\Extension\Extension[]
diff --git a/core/lib/Drupal/Core/Extension/ThemeInstallerInterface.php b/core/lib/Drupal/Core/Extension/ThemeInstallerInterface.php
index 37b4ce6..192979a 100644
--- a/core/lib/Drupal/Core/Extension/ThemeInstallerInterface.php
+++ b/core/lib/Drupal/Core/Extension/ThemeInstallerInterface.php
@@ -7,6 +7,9 @@
 
 namespace Drupal\Core\Extension;
 
+/**
+ * Manages theme installation/uninstallation.
+ */
 interface ThemeInstallerInterface {
 
   /**