Seems that this is better solution to the #245 (output buffering)

This works for both, when output_buffering is enabled, and disabled

Author: slawkens

install/tools/5-database.php

@@ -11,10 +11,10 @@
 require BASE . 'install/includes/config.php';
 
 ini_set('max_execution_time', 300);
-if(ob_get_length() > 0) {
-	ob_implicit_flush();
-	ob_end_flush();
-}
+
+@ob_end_flush();
+ob_implicit_flush();
+
 header('X-Accel-Buffering: no');
 
 if(!$error) {

install/tools/7-finish.php

@@ -12,10 +12,10 @@
 require BASE . 'install/includes/locale.php';
 
 ini_set('max_execution_time', 300);
-if(ob_get_length() > 0) {
-	ob_implicit_flush();
-	ob_end_flush();
-}
+
+@ob_end_flush();
+ob_implicit_flush();
+
 header('X-Accel-Buffering: no');
 /*
 if(isset($config['installed']) && $config['installed'] && !isset($_SESSION['saved'])) {