bug#44329: 28.0.50; Crash in bidi_mirror_char on view-hello-file when no bidi-display-reordering (harfbuzz)

[Eli Zaretskii]

> From: Stefan Kangas <stefankangas@gmail.com>
> Date: Fri, 30 Oct 2020 23:29:58 +0000
> Cc: 44329@debbugs.gnu.org
> 
>        The buffer-local variable ‘bidi-display-reordering’ controls whether
>     text in the buffer is reordered for display.  If its value is non-‘nil’,
>     Emacs reorders characters that have right-to-left directionality when
>     they are displayed.  The default value is ‘t’.
> 
> Should we just remove it from the manual, if it's only useful for
> debugging?  Or add a warning similar to the one in the docstring?

I don't think it will matter either way.  The Internet is full of
advice to turn it off, and nothing we do at this point can change
that.  Better stop wasting our own resources on this.