In a discussion in 2015 the follow was proposed:
Please modify the function "theme_essential_print_single_section_page" in page "/essential/lib.php" as follows:
Change following code as
// Close single-section div.
echo html_writer::end_tag('div');
TO
echo $sectionnav;
// Close single-section div.
echo html_writer::end_tag('div');
But now it is 2019 and I am using Moodle 3.5.3 en Essential theme 3.5.1.4
Cannot find the code in "/essential/lib.php"
Does anyone know if this is moved to somewhere else.