Why does the script go to require and not return?

Question

PHP

There is a code

echo '<!-- test 1-->'; 
require($_SERVER["DOCUMENT_ROOT"]."/bitrix/header.php"); 
echo '<!-- test 3-->';

At the end of header.php added echo '';
It prints test 1 , test 2... but test 3 doesn't.
There are no errors.

Answer 1

Use a tracer (Xdebug for example) and see where the stop is.
Well, there should be something in the web server error logs.