On 22.05 and 21.11 clicking help from system preferences points to: https://koha-community.org/manual//22.05/en/html/systempreferences.html which is a 404 It should point to: https://koha-community.org/manual//22.05/en/html/globalpreferences.html
This will be corrected in 22.11, see https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=31465. Meanwhile, you might edit /usr/share/koha/lib/Koha/Manual.pm as a workaround and change the lines: 'admin/preferences' => '/globalpreferences.html', (from systempreferences.html) and 'admin/systempreferences' => '/localusepreferences.html' (from systempreferences.html#local-use).
*** This bug has been marked as a duplicate of bug 31465 ***