bug#38601: describe-mode never says the most important thing

[積丹尼 Dan Jacobson]

>>>>> "EZ" == Eli Zaretskii <eliz@gnu.org> writes:
>> The problem is, it doesn't mention how to turn it on and off!

EZ> Actually, it does: that's the last sentence above.

OK, but e.g., the next one doesn't:
^L
File-Name-Shadow minor mode (no indicator):
Toggle file-name shadowing in minibuffers (File-Name Shadow mode).
With a prefix argument ARG, enable File-Name Shadow mode if ARG
is positive, and disable it otherwise.  If called from Lisp,
enable the mode if ARG is omitted or nil.

File-Name Shadow mode is a global minor mode.  When enabled, any
part of a filename being read in the minibuffer that would be
ignored (because the result is passed through
‘substitute-in-file-name’) is given the properties in
‘file-name-shadow-properties’, which can be used to make that
portion dim, invisible, or otherwise less visually noticeable.
^L

It talks about a prefix argument but doesn't show one how to invoke it.