Add a test course small is enough
cd moodle/dirroot
php admin/tool/generator/cli/maketestsite.php --size=S
Make note of the new course id
Add sleep(10); to line 141 of report/outline/index.php (straight after \core\session\manager::write_close(); )
Navigate in browser to report/outline/index.php?id=XX (use the new course id here)
While this page is loading, open another page from the site in a new tab and confirm should load straight away.
This can be a very slow report and clogs up the session
has a non-specific relationship to
MDL-68644mod/quiz/report.php should write_close the session