Issue #2458925 by alexpott: Screen is black and completely unreadable in...

Issue #2458925 by alexpott: Screen is black and completely unreadable in Configure page after install on standard profile

core/includes/install.core.inc

@@ -1611,21 +1611,13 @@ function install_profile_modules(&$install_state) {
  *   An array of information about the current installation state.
  */
 function install_profile_themes(&$install_state) {
-  $theme_handler = \Drupal::service('theme_handler');
-
-  // ThemeHandler::install() resets the current list of themes. The theme used
-  // in the installer is not necessarily in the list of themes to install, so
-  // retain the current list.
-  // @see _drupal_maintenance_theme()
-  $current_themes = $theme_handler->listInfo();
-
   // Install the themes specified by the installation profile.
   $themes = $install_state['profile_info']['themes'];
-  $theme_handler->install($themes);
+  \Drupal::service('theme_handler')->install($themes);
 
-  foreach ($current_themes as $theme) {
-    $theme_handler->addTheme($theme);
-  }
+  // Ensure that the install profile's theme is used.
+  // @see _drupal_maintenance_theme()
+  \Drupal::service('theme.manager')->resetActiveTheme();
 }
 
 /**
@@ -1644,6 +1636,10 @@ function install_install_profile(&$install_state) {
   // optional configuration whose dependencies can be met at this point removes
   // any disparities that this creates.
   \Drupal::service('config.installer')->installOptionalConfig();
+
+  // Ensure that the install profile's theme is used.
+  // @see _drupal_maintenance_theme()
+  \Drupal::service('theme.manager')->resetActiveTheme();
 }
 
 /**

core/includes/theme.maintenance.inc

@@ -68,11 +68,10 @@ function _drupal_maintenance_theme() {
   // installed, retrieve all available themes.
   /** @var \Drupal\Core\Theme\ThemeInitialization $theme_init */
   $theme_init = \Drupal::service('theme.initialization');
+  $theme_handler = \Drupal::service('theme_handler');
   if (empty($themes) || !isset($themes[$custom_theme])) {
-    $theme_handler = \Drupal::service('theme_handler');
     $themes = $theme_handler->rebuildThemeData();
     $theme_handler->addTheme($themes[$custom_theme]);
-    \Drupal::theme()->setActiveTheme($theme_init->getActiveTheme($themes[$custom_theme], array()));
   }
 
   // \Drupal\Core\Extension\ThemeHandlerInterface::listInfo() triggers a
@@ -86,8 +85,12 @@ function _drupal_maintenance_theme() {
   $base_theme = array();
   $ancestor = $theme;
   while ($ancestor && isset($themes[$ancestor]->base_theme)) {
-    $base_theme[] = $new_base_theme = $themes[$themes[$ancestor]->base_theme];
+    $base_theme[] = $themes[$themes[$ancestor]->base_theme];
     $ancestor = $themes[$ancestor]->base_theme;
+    if ($ancestor) {
+      // Ensure that the base theme is added.
+      $theme_handler->addTheme($themes[$ancestor]);
+    }
   }
   // @todo This is just a workaround. Find a better way how to handle themes
   //   on maintenance pages, see https://www.drupal.org/node/2322619.

core/modules/system/src/Tests/Installer/StandardInstallerTest.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\system\Tests\Installer\StandardInstallerTest.
+ */
+
+namespace Drupal\system\Tests\Installer;
+
+use Drupal\simpletest\InstallerTestBase;
+
+/**
+ * Tests the interactive installer installing the standard profile.
+ *
+ * @group Installer
+ */
+class StandardInstallerTest extends InstallerTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $profile = 'standard';
+
+  /**
+   * Ensures that the user page is available after installation.
+   */
+  public function testInstaller() {
+    // Verify that the confirmation message appears.
+    require_once \Drupal::root() . '/core/includes/install.inc';
+    $this->assertRaw(t('Congratulations, you installed @drupal!', array(
+      '@drupal' => drupal_install_profile_distribution_name(),
+    )));
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUpSite() {
+    // Test that the correct theme is being used.
+    $this->assertNoRaw('bartik');
+    $this->assertRaw('themes/seven/css/theme/install-page.css');
+    parent::setUpSite();
+  }
+
+
+}