.../Drupal/Core/Test/FunctionalTestSetupTrait.php  | 28 ++++++----------------
 core/modules/simpletest/src/WebTestBase.php        |  4 +++-
 .../TestSite/Commands/TestSiteInstallCommand.php   |  4 +++-
 core/tests/Drupal/Tests/BrowserTestBase.php        |  4 +++-
 .../Tests/Listeners/DeprecationListenerTrait.php   |  2 +-
 5 files changed, 17 insertions(+), 25 deletions(-)

diff --git a/core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php b/core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
index 0c02f9a2a6..fdf785e9d0 100644
--- a/core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
+++ b/core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
@@ -362,29 +362,15 @@ protected function initConfig(ContainerInterface $container) {
       ->set('timezone.default', 'Australia/Sydney')
       ->save();
 
-    if (empty($this->theme)) {
-      @trigger_error('Drupal\Tests\BrowserTestBase::$theme is required in drupal:9.0.0. See https://www.drupal.org/node/2352949', E_USER_DEPRECATED);
-      if ($this->profile === 'demo_umami') {
-        $this->theme = 'umami';
-      }
-      elseif ($this->profile === 'standard') {
-        $this->theme = 'bartik';
-      }
-      elseif ($this->profile === 'minimal') {
-        $this->theme = 'stark';
-      }
-      elseif ($this->profile === 'testing') {
-        $this->theme = 'classy';
-        $config->getEditable('system.theme')->clear('admin')->save();
-      }
-      else {
+    if ($this->profile === 'testing' && empty($this->theme)) {
+      @trigger_error('Drupal\Tests\BrowserTestBase::$theme is required in drupal:9.0.0 when using the default "testing" install profile. See https://www.drupal.org/node/2352949, which includes recommendations on which theme to use', E_USER_DEPRECATED);
+      $this->theme = 'classy';
+      $config->getEditable('system.theme')
         // @see core/modules/system/config/install/system.theme.yml
-        $this->theme = 'stark';
-      }
+        ->clear('admin')
+        ->set('default', $this->theme)
+        ->save();
     }
-    $config->getEditable('system.theme')
-      ->set('default', $this->theme)
-      ->save();
   }
 
   /**
diff --git a/core/modules/simpletest/src/WebTestBase.php b/core/modules/simpletest/src/WebTestBase.php
index 3ca58688e1..1b37ed434c 100644
--- a/core/modules/simpletest/src/WebTestBase.php
+++ b/core/modules/simpletest/src/WebTestBase.php
@@ -392,7 +392,9 @@ protected function setUp() {
     // Initialize and override certain configurations.
     $this->initConfig($container);
 
-    $this->installThemeFromClassProperty($container);
+    if ($this->profile === 'testing') {
+      $this->installThemeFromClassProperty($container);
+    }
 
     // Collect modules to install.
     $this->installModulesFromClassProperty($container);
diff --git a/core/tests/Drupal/TestSite/Commands/TestSiteInstallCommand.php b/core/tests/Drupal/TestSite/Commands/TestSiteInstallCommand.php
index b4cd21e328..a6a84d27ef 100644
--- a/core/tests/Drupal/TestSite/Commands/TestSiteInstallCommand.php
+++ b/core/tests/Drupal/TestSite/Commands/TestSiteInstallCommand.php
@@ -198,7 +198,9 @@ protected function installDrupal() {
     $this->initSettings();
     $container = $this->initKernel(\Drupal::request());
     $this->initConfig($container);
-    $this->installThemeFromClassProperty($container);
+    if ($this->profile === 'testing') {
+      $this->installThemeFromClassProperty($container);
+    }
     $this->installModulesFromClassProperty($container);
     $this->rebuildAll();
   }
diff --git a/core/tests/Drupal/Tests/BrowserTestBase.php b/core/tests/Drupal/Tests/BrowserTestBase.php
index 617e326fbf..62e8026389 100644
--- a/core/tests/Drupal/Tests/BrowserTestBase.php
+++ b/core/tests/Drupal/Tests/BrowserTestBase.php
@@ -564,7 +564,9 @@ public function installDrupal() {
     $this->initSettings();
     $container = $this->initKernel(\Drupal::request());
     $this->initConfig($container);
-    $this->installThemeFromClassProperty($container);
+    if ($this->profile === 'testing') {
+      $this->installThemeFromClassProperty($container);
+    }
     $this->installModulesFromClassProperty($container);
     $this->rebuildAll();
   }
diff --git a/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php b/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
index da5256c82f..a4c60fbd00 100644
--- a/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
+++ b/core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
@@ -141,7 +141,7 @@ public static function getSkippedDeprecations() {
       // symfony/browser-kit to 4.3+.
       'The "Symfony\Component\BrowserKit\Response::getStatus()" method is deprecated since Symfony 4.3, use getStatusCode() instead.',
       // @todo Remove in …
-      'Drupal\Tests\BrowserTestBase::$theme is required in drupal:9.0.0. See https://www.drupal.org/node/2352949',
+      'Drupal\Tests\BrowserTestBase::$theme is required in drupal:9.0.0 when using the default "testing" install profile. See https://www.drupal.org/node/2352949, which includes recommendations on which theme to use',
     ];
   }