diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index d0aee7ed..d77cc748 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -2010,9 +2010,6 @@
     </PossiblyUnusedMethod>
   </file>
   <file src="test/StringToLowerTest.php">
-    <InvalidArgument>
-      <code><![CDATA[$e->getMessage()]]></code>
-    </InvalidArgument>
     <PossiblyUnusedMethod>
       <code><![CDATA[returnUnfilteredDataProvider]]></code>
     </PossiblyUnusedMethod>
diff --git a/test/StringToLowerTest.php b/test/StringToLowerTest.php
index 26a62c4c..65f8019f 100644
--- a/test/StringToLowerTest.php
+++ b/test/StringToLowerTest.php
@@ -110,7 +110,7 @@ public function testCaseInsensitiveEncoding(): void
                 self::assertSame($output, $filter($input));
             }
         } catch (Exception\ExtensionNotLoadedException $e) {
-            self::assertContains('mbstring is required', $e->getMessage());
+            self::assertStringContainsString('mbstring is required', $e->getMessage());
         }
     }