diff --git a/tests/ElasticApmTests/Util/AssertMessageStack.php b/tests/ElasticApmTests/Util/AssertMessageStack.php
index 56883efa3..66a1ca56d 100644
--- a/tests/ElasticApmTests/Util/AssertMessageStack.php
+++ b/tests/ElasticApmTests/Util/AssertMessageStack.php
@@ -39,7 +39,7 @@
 final class AssertMessageStack implements LoggableInterface
 {
     /** @var bool */
-    private static $isEnabled = true;
+    private static $isEnabled = false;
 
     /** @var ?AssertMessageStack */
     private static $singleton = null;
diff --git a/tests/ElasticApmTests/Util/StackTraceFrameExpectations.php b/tests/ElasticApmTests/Util/StackTraceFrameExpectations.php
index 284f3fedf..2f46b5182 100644
--- a/tests/ElasticApmTests/Util/StackTraceFrameExpectations.php
+++ b/tests/ElasticApmTests/Util/StackTraceFrameExpectations.php
@@ -122,10 +122,11 @@ public static function fromClosure(string $fileName, int $lineNumber, ?string $n
         if (PHP_VERSION_ID < 80400) {
             $result = self::fromClassMethodUnknownLocation($class, $isStatic, ($namespace === null ? '' : ($namespace . '\\')) . '{closure}');
         } else {
-            $result = self::fromClassMethodUnknownLocation($class, $isStatic, '{closure:' . $class . '::__METHOD__():__LINE__}');
+            $result = self::fromClassMethodUnknownLocation($class, $isStatic, '{closure:__CLASS__::__METHOD__():__LINE__}');
             $expectedFunc = $result->function->getValue();
             TestCaseBase::assertNotNull($expectedFunc);
             $expectedFuncRegex = self::convertFunctionNameToRegPattern($expectedFunc);
+            $expectedFuncRegex = str_replace('__CLASS__', '[a-zA-Z0-9\\\\]+', $expectedFuncRegex);
             $expectedFuncRegex = str_replace('__METHOD__', '[a-zA-Z0-9]+', $expectedFuncRegex);
             $expectedFuncRegex = str_replace('__LINE__', '[0-9]+', $expectedFuncRegex);
             $result->function->setValue($expectedFuncRegex);