diff --git a/libraries/src/Exception/ExceptionHandler.php b/libraries/src/Exception/ExceptionHandler.php
index 7ad3c6375410f..ab96f5e7287ca 100644
--- a/libraries/src/Exception/ExceptionHandler.php
+++ b/libraries/src/Exception/ExceptionHandler.php
@@ -94,8 +94,14 @@ public static function render($error)
 				// Push the error object into the document
 				$document->setError($error);
 
-				// Clear buffered output at all levels in non-test mode
-				$callerFunction = static::getCallerFunctionName();
+				// Clear buffered output at all levels
+				while (ob_get_level())
+				{
+					ob_end_clean();
+				}
+
+				// This is needed to ensure the test suite can still get the output buffer 
+				ob_start();
 
 				$document->setTitle(Text::_('ERROR') . ': ' . $error->getCode());
 
@@ -176,7 +182,7 @@ public static function render($error)
 	protected static function getCallerFunctionName()
 	{
 		$backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
-		
+
 		return isset($backtrace[2]['function']) ? $backtrace[2]['function'] : false;
 	}