diff --git a/core/modules/file/migration_templates/d7_file_private.yml b/core/modules/file/migration_templates/d7_file_private.yml
index 290f367..9c6b8e2 100644
--- a/core/modules/file/migration_templates/d7_file_private.yml
+++ b/core/modules/file/migration_templates/d7_file_private.yml
@@ -29,9 +29,6 @@ process:
       - '@source_full_path'
       - uri
   filemime: filemime
-  # filesize is dynamically computed when file entities are saved, so there is
-  # no point in migrating it.
-  # filesize: filesize
   status: status
   # Drupal 7 didn't keep track of the file's creation or update time -- all it
   # had was the vague "timestamp" column. So we'll use it for both.
diff --git a/core/modules/file/tests/src/Kernel/Migrate/d7/MigratePrivateFileTest.php b/core/modules/file/tests/src/Kernel/Migrate/d7/MigratePrivateFileTest.php
index bb5f17c..7b6f763 100644
--- a/core/modules/file/tests/src/Kernel/Migrate/d7/MigratePrivateFileTest.php
+++ b/core/modules/file/tests/src/Kernel/Migrate/d7/MigratePrivateFileTest.php
@@ -8,12 +8,15 @@
 use Drupal\Tests\migrate_drupal\Kernel\d7\MigrateDrupal7TestBase;
 
 /**
- * Migrates all files in the file_managed table.
+ * Tests private files migration.
  *
  * @group file
  */
 class MigratePrivateFileTest extends MigrateDrupal7TestBase {
 
+  /**
+   * {@inheritdoc}
+   */
   public static $modules = ['file'];
 
   /**
@@ -72,10 +75,10 @@ public function register(ContainerBuilder $container) {
   protected function assertEntity($id, $name, $uri, $mime, $size, $created, $changed, $uid) {
     /** @var \Drupal\file\FileInterface $file */
     $file = File::load($id);
-    $this->assertTrue($file instanceof FileInterface);
+    $this->assertInstanceOf(FileInterface::class, $file);
     $this->assertSame($name, $file->getFilename());
     $this->assertSame($uri, $file->getFileUri());
-    $this->assertTrue(file_exists($uri));
+    $this->assertFileExists($uri);
     $this->assertSame($mime, $file->getMimeType());
     $this->assertSame($size, $file->getSize());
     // isPermanent(), isTemporary(), etc. are determined by the status column.
diff --git a/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php b/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php
index 5c73d66..c87247e 100644
--- a/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php
+++ b/core/modules/migrate_drupal_ui/src/Form/MigrateUpgradeForm.php
@@ -956,9 +956,6 @@ public function buildCredentialForm(array $form, FormStateInterface $form_state)
       '#title' => $this->t('Files directory'),
       '#description' => $this->t('To import files from your current Drupal site, enter a local file directory containing your site (e.g. /var/www/docroot), or your site address (for example http://example.com).'),
       '#states' => [
-        'invisible' => [
-          ':input[name="version"]' => ['value' => 7],
-        ],
         'visible' => [
           ':input[name="version"]' => ['value' => 6],
         ],
@@ -970,9 +967,6 @@ public function buildCredentialForm(array $form, FormStateInterface $form_state)
       '#title' => $this->t('Public files directory'),
       '#description' => $this->t('To import public files from your current Drupal site, enter a local file directory containing your site (e.g. /var/www/docroot), or your site address (for example http://example.com).'),
       '#states' => [
-        'invisible' => [
-          ':input[name="version"]' => ['value' => 6],
-        ],
         'visible' => [
           ':input[name="version"]' => ['value' => 7],
         ],
@@ -985,9 +979,6 @@ public function buildCredentialForm(array $form, FormStateInterface $form_state)
       '#default_value' => '',
       '#description' => $this->t('To import private files from your current Drupal site, enter a local file directory containing your site (e.g. /var/www/docroot).'),
       '#states' => [
-        'invisible' => [
-          ':input[name="version"]' => ['value' => 6],
-        ],
         'visible' => [
           ':input[name="version"]' => ['value' => 7],
         ],