diff -u b/src/PanelsEvents.php b/src/PanelsEvents.php
--- b/src/PanelsEvents.php
+++ b/src/PanelsEvents.php
@@ -25,7 +25,8 @@
    *
    * This event allows modules to react after a Panels display variant is saved.
    * The event listener method receives a \Drupal\panels\PanelsVariantEvent
-   * instance.
+   * instance. Note that changes to the variant made by subscribers to this
+   * event will NOT be persisted.
    *
    * @Event
    *
diff -u b/tests/src/Kernel/PanelsStorageManagerTest.php b/tests/src/Kernel/PanelsStorageManagerTest.php
--- b/tests/src/Kernel/PanelsStorageManagerTest.php
+++ b/tests/src/Kernel/PanelsStorageManagerTest.php
@@ -3,6 +3,8 @@
 namespace Drupal\Tests\panels\Kernel;
 
 use Drupal\KernelTests\KernelTestBase;
+use Drupal\page_manager\Entity\Page;
+use Drupal\page_manager\Entity\PageVariant;
 use Drupal\panels\PanelsEvents;
 use Drupal\panels\PanelsVariantEvent;
 
@@ -25,45 +27,40 @@
     $event_dispatcher = $this->container->get('event_dispatcher');
 
     $event_dispatcher->addListener(PanelsEvents::VARIANT_PRE_SAVE, function (PanelsVariantEvent $event) {
-      $event->getVariant()->testPreSave = TRUE;
+      $event->getVariant()->setPageTitle('Gentlefolk, BEHOLD!');
     });
     $event_dispatcher->addListener(PanelsEvents::VARIANT_POST_SAVE, function (PanelsVariantEvent $event) {
-      $event->getVariant()->testPostSave = TRUE;
+      $event->getVariant()->setPageTitle('This will be discarded.');
     });
 
-    /** @var \Drupal\page_manager\PageInterface $page */
-    $page = $this->container
-      ->get('entity_type.manager')
-      ->getStorage('page')
-      ->create([
-        'id' => $this->randomMachineName(),
-        'label' => $this->randomMachineName(),
-        'path' => '/' . $this->randomMachineName(),
-      ]);
+    $page = Page::create([
+      'id' => $this->randomMachineName(),
+      'label' => $this->randomMachineName(),
+      'path' => '/' . $this->randomMachineName(),
+    ]);
     $page->save();
 
-    /** @var \Drupal\page_manager\PageVariantInterface $variant */
-    $variant = $this->container
-      ->get('entity_type.manager')
-      ->getStorage('page_variant')
-      ->create([
-        'id' => $this->randomMachineName(),
-        'label' => $this->randomMachineName(),
-        'variant' => 'panels_variant',
-        'variant_settings' => [
-          'storage_type' => 'page_manager',
-          'storage_id' => $this->randomMachineName(),
-          'layout' => 'layout_onecol',
-          'layout_settings' => [],
-        ],
-        'page' => $page->id(),
-      ]);
+    $variant = PageVariant::create([
+      'id' => 'stunning',
+      'label' => $this->randomMachineName(),
+      'variant' => 'panels_variant',
+      'variant_settings' => [
+        'page_title' => 'Pastafazoul',
+        'storage_type' => 'page_manager',
+        'storage_id' => $this->randomMachineName(),
+        'layout' => 'layout_onecol',
+        'layout_settings' => [],
+      ],
+      'page' => $page->id(),
+    ]);
     $variant->save();
 
-    $display = $variant->getVariantPlugin();
-    $this->container->get('panels.storage_manager')->save($display);
-    $this->assertObjectHasAttribute('testPreSave', $display);
-    $this->assertObjectHasAttribute('testPostSave', $display);
+    $this->container->get('panels.storage_manager')->save($variant->getVariantPlugin());
+
+    // The page title set by the pre-save event handler should be persisted;
+    // the one set by the post-save handler should be discarded.
+    $page_title = PageVariant::load('stunning')->getVariantPlugin()->getPageTitle();
+    $this->assertSame('Gentlefolk, BEHOLD!', $page_title);
   }
 
 }