bug#50983: 28.0.50; [REGRESSION, BUG] Display bugs with uncommon characters

[Eli Zaretskii]

> From: Rudi C <rudiwillalwaysloveyou@gmail.com>
> Date: Sun, 3 Oct 2021 14:30:56 +0330
> 
> Also, can you be more specific about where you do observe the bugs? In TUI 
> emacs on iTerm? 
> 
> I can confirm that the bug with `weird.txt` happens on iTerm, too, again with 
> both emacs and neovim! But the
> bug with `bug.txt` does not happen in iTerm, only on Kitty.

This sounds like the terminal emulators have a problem in supporting
unusual Unicode characters, such as zero-width or double-width
characters, perhaps?  I see no Emacs problem here, since it happens
only on some terminal emulators and not on others.