Where does the redirect with SEF_APPLICATION_CUR_PAGE_URL come from?

Question

1C-Bitrix

Yesterday I closed the site with the page /section/page/, today I open it and there /bitrix/urlrewrite.php?SEF_APPLICATION_CUR_PAGE_URL=/section/page/ I understand
how it works. Where did it come from?
This is definitely not a standard component, for example, when submitting a form, it was redirected - the standard components are not used. All page and component code is completely mine.
It remains to be assumed that this is some kind of rubbish that crawled through

$APPLICATION->ShowHeadStrings();
$APPLICATION->ShowHeadScripts();

How to fix?

Answer 1

I still didn’t find where this comes from (I didn’t look much), I just hung a handler on the OnBeforeProlog event:

if ($_REQUEST['SEF_APPLICATION_CUR_PAGE_URL']
                && $_REQUEST['AUTH_FORM'] == 'Y'
                && $_REQUEST['TYPE'] == 'AUTH') {
            global $USER;
            if ($USER->IsAuthorized()) {
                LocalRedirect($_REQUEST['SEF_APPLICATION_CUR_PAGE_URL']);
            }
        }

There seems to be no problem.