diff --git a/core_search_facets/src/Tests/WebTestBase.php b/core_search_facets/src/Tests/WebTestBase.php
index b12ca90..f9ffb0c 100644
--- a/core_search_facets/src/Tests/WebTestBase.php
+++ b/core_search_facets/src/Tests/WebTestBase.php
@@ -18,15 +18,6 @@ abstract class WebTestBase extends SimpletestWebTestBase {
   use StringTranslationTrait;
 
   /**
-   * Exempt from strict schema checking.
-   *
-   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
-   *
-   * @var bool
-   */
-  protected $strictConfigSchema = FALSE;
-
-  /**
    * Modules to enable for this test.
    *
    * @var string[]
diff --git a/src/Tests/WebTestBase.php b/src/Tests/WebTestBase.php
index 3b06261..562857c 100644
--- a/src/Tests/WebTestBase.php
+++ b/src/Tests/WebTestBase.php
@@ -21,15 +21,6 @@ abstract class WebTestBase extends SimpletestWebTestBase {
   use ExampleContentTrait;
 
   /**
-   * Exempt from strict schema checking.
-   *
-   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
-   *
-   * @var bool
-   */
-  protected $strictConfigSchema = FALSE;
-
-  /**
    * Modules to enable for this test.
    *
    * @var string[]