bug#57566: 13.1.4; Disappearing content when previewing inline math with LuaTeX

[Ikumi Keita]

Hi Michael,

>>>>> "Braun, Michael" <braunm@mail.smu.edu> writes:
> Here's a MWE:

> \documentclass{standalone}
> \begin{document}

> AA $\alpha$ BB $\beta$ GG $\gamma$ DD $\Delta$.

> \end{document}

> Let's say I open this file and (preview-buffer). Then, I click on the
> gamma symbol (which auto-reveals), edit the preview area to $\gamma +
> 1$, and run (preview-at-point). The $\gamma+1$ renders correctly, but
> everything up to, but not including, AA disappears. So all I see is
> "AA <\gamma+1> DD <\Delta>" (where < ... > is the rendered math
> expression).

> The "$\alpha$ BB $\beta$ GG" is now hidden under the preview area for
> <gamma+1>. I need to (preview-clearout-at-point) to get it all back.
> It looks like when preview looks backwards, it is indeed extending
> through all unmodified previews back to the beginning of the line, but
> is showing only the rightmost preview that I edited.

Thank you for the report. I can confirm the issue. It seems that the
origin is the same as bug#54200[1]. Lualatex emits log message in
slightly different format from the one of pdflatex.

Unfortunately, the luatex developper isn't eager to fix this issue
as you can read in [1]. I'm afraid that it won't be fixed in the near
future. :-(

You can try ad-hoc work around provided in [1], but note that
1. It isn't sure that the hard-coded value of 2 is valid for other
   cases.
2. It breaks for other engines than lualatex.

[1] https://debbugs.gnu.org/54200

Regards,
Ikumi Keita
#StandWithUkraine #StopWarInUkraine