only in patch2:
unchanged:
--- a/core/modules/block/src/Tests/Migrate/d6/MigrateBlockTest.php
+++ b/core/modules/block/src/Tests/Migrate/d6/MigrateBlockTest.php
@@ -80,7 +80,7 @@ protected function setUp() {
    */
   public function testBlockMigration() {
     $blocks = Block::loadMultiple();
-    $this->assertIdentical(count($blocks), 10);
+    $this->assertIdentical(11, count($blocks));
 
     // User blocks
     $test_block_user = $blocks['user'];
@@ -179,5 +179,13 @@ public function testBlockMigration() {
     $visibility = $test_block_block_3->getVisibility();
     $this->assertTrue(empty($visibility));
     $this->assertIdentical(-2, $test_block_block_3->getWeight());
+    
+    $test_block_block_4 = $blocks['block_4'];
+    $this->assertNotNull($test_block_block_4);
+    $this->assertIdentical('right', $test_block_block_4->getRegion());
+    $this->assertIdentical('test_theme_99', $test_block_block_4->getTheme());
+    $visibility = $test_block_block_4->getVisibility();
+    $this->assertTrue(empty($visibility));
+    $this->assertIdentical(-99, $test_block_block_4->getWeight());
   }
 }