bug#66390: `man' allows to inject arbitrary shell code

[Stefan Kangas]

Eli Zaretskii <eliz@gnu.org> writes:

> Does it also work correctly in all the scenarios described in
> bug#64795, including completion?

No, trying to complete there gives the prompt:

    Manual entry: [ [No match]

On the other hand this already seems broken in a different way in Emacs
29 on this macOS machine.  Trying to complete with:

    M-x man RET [ TAB TAB

leads to

    Manual entry: [: [Sole completion]

and RET at this point gives

    Can't find the [: manpage