Memory-related cleanups
As outlined in #3443 (closed), this MR only updates documentation because main
is otherwise fine.
The changes in this MR attempt to make the documentation for the -M
command-line option on main
more consistent with the revised version
of the relevant part of the man page proposed for v9_16
in !6569 (merged).
Closes #3443 (closed)
Edited by Michał Kępień