On the editing help page if a section is expandable mouse cursor displayed as a hand in collapsed state so clicking on the section body expand the section:
Non-expandable section has normal cursor, i.e. arrow:
But the section "Bare URLs" has a hand cursor being non-expandable (clicking do nothing):
Perhaps previously this section was expandable, and when has changed mouse over cursor is not changed to corresponding state. I didn't look into HTML source :) just speculating.
Visiting the Bare URLs section via direct link (or via page content block on the right hand side of the page) fix the issue due to changing the section currect style as expanded (checked on other actually expandable sections).