[tex4ht] DVI error: stack empty at pop command, with tex4ht, only when using \usepackage[libertine]{newtxmath}

[Nasser M. Abbasi]

I just found new problem. Using tex4ht on TL 2017.

On one file I have, I can get tex4t to show this error

------------
......
processing page 183
   graphic size: 63.8874pt x 26.5726pt (22.4538mm x 9.33921mm)
   output written to report-0183.svg
processing page 184
   DVI error: stack empty at pop command
Make4ht: tex4ht  -cmozhtf -utf8 "report.dvi" can be executed only 1x
Make4ht: t4ht  -p "report.dvi" can be executed only 1x
Parse LG
.....
mv report-0182.svg re176x.svg
mv report-0183.svg re177x.svg
Image processing error: max_count exceeded
Image processing error: max_count exceeded
Image processing error: max_count exceeded
Image processing error: max_count exceeded
.....
-------------------

I've seen this problem before, 2016.

"tex4ht] Too many DVI errors. stack empty at pop command"
http://tug.org/pipermail/tex4ht/2016q1/001341.html

If I simply comment out these 2 lines for tex4ht run:

%\usepackage[T1]{fontenc}
%\usepackage[libertine]{newtxmath}

Then the error goes away.  I noticed when these lines
are there, there are lots of font issues show in the log file,
this is before the DVI error, like this

----------------------
--- warning --- File `cmsy.htf' starts/ends with character code 127 (instead of 222)
--- warning --- File `cmsy.htf' starts/ends with character code 127 (instead of 222)
(/usr/local/texlive/2017/texmf-dist/fonts/tfm/public/newtx/fxlri-5letters.tfm)
(/usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/alias/libertine/fxl.htf)
Searching `lm-ec.htf' for `fxlri-5letters.htf'
(/usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/unicode/lm/lm-ec.htf)
(/usr/local/texlive/2017/texmf-dist/fonts/tfm/public/newtx/fxlri-7letters.tfm)
(/usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/alias/libertine/fxl.htf)
Searching `lm-ec.htf' for `fxlri-7letters.htf'
(/usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/unicode/lm/lm-ec.htf)
(/usr/local/texlive/2017/texmf-dist/fonts/tfm/public/newtx/zxlri-8r.tfm)
--- warning --- Couldn't find font `zxlri-8r.htf' (char codes: 17--181)
.....
---------------------------

I do not know if the above font warnings and errors is what
iscausing the DVI error.

For now, I simply do the following to avoid the problem

----------------------
\ifdefined\HCode
\else
\usepackage[T1]{fontenc}
\usepackage[libertine]{newtxmath}
\fi
----------------

And now everything works well. tex4ht is happy.

I do not know how to make a MWE now, since this file is large,
contains 170 equations, about 290 pages.  On a small file,
this error do not show up.

I could do the following: Make a zip file that contains
this self contained one latex file, and the main.mk4 file I
use and the .cfg file and the command I used to compile it if
someone wants to try to repoduce it.

My compile command is

make4ht --shell-escape --lua -u -c nma.cfg  -e main.mk4 foo.tex "htm,3,pic-align,notoc*"

Would this be OK? If someone feels it is important to look
why the DVI shows up only when using newtxmath. But
if it is known that tex4ht simply does not support this package,
then I do not need to do this.

Thanks
--Nasser