bug#45915: 28.2; delete-char deletes two letters

[Eli Zaretskii]

> Cc: tkk@misasa.okayama-u.ac.jp, Ihor Radchenko <yantar92@gmail.com>
> From: Tak Kunihiro <homeros.misasa@gmail.com>
> Date: Sat, 17 Sep 2022 12:48:56 +0900
> 
> I see a light.
> With the following patch, <delete> deletes only a letter.
> 
> The (org-table-align) inserts string with text properties.
> It seems that the text properties matter.
> 
> However, I do not understand what's going on there. Can you take a look
> (org-table-align) with this hint and revise it in correct way?

Why do you think your proposed change is incorrect?

Rather than asking us to study how org-table works and why it
misbehaves in this case, would it be possible for some Org expert to
explain that in simple terms, so that the relation of what happens to
the relevant core Emacs features could be easier to realize?  For
example, what are the text properties involved in this case, the ones
that substring-no-properties removes?  Is it possible that one of
these properties is 'composition'?