[tex4ht] how to make \usepackage{newtxtext} work with tex4ht? it removes "fi" and "ff" from text

[Nasser M. Abbasi]

Fyi;

update. I also found that \usepackage{newtxmath} causes problem as well

------------------------------
\documentclass[12pt]{article}%
\usepackage{newtxmath}
\begin{document}
$z=\tan{x}$
\end{document}
----------------------

htlatex foo.tex  gives

(/usr/local/texlive/2015/texmf-dist/tex4ht/base/unix/tex4ht.env)
(/usr/local/texlive/2015/texmf-dist/tex4ht/ht-fonts/iso8859/1/charset/unicode.4hf)
(/usr/local/texlive/2015/texmf-dist/fonts/tfm/public/newtx/ntxmia.tfm)
--- warning --- Couldn't find font `ntxmia.htf' (char codes: 0--255)

It looks likenewtxmath and newtxtext can not be used with tex4ht.
Is it too hard to make them work in tex4ht? The math looked better
with them (in pdf) and was hoping to use them in HTML as well.

thanks,
--Nasser

On 7/1/2015 4:11 PM, Nasser M. Abbasi wrote:
> When I compile this MWE
>
> -----------------------------
> \documentclass[12pt]{article}
> \usepackage{newtxtext}
> \begin{document}
>         find differential
> \end{document}
> -------------------------
> The HTML shows
>
>         nd dierential
>
> So the "fi" and "ff" are gone. (looking at the HTML source code itself,
> I see strange looking things where these letters are supposed to be,
> like small squares with 4 dots in them)
>
> I see these errors/messages
>
> ----------------------------
> tex4ht.c (2012-07-25-19:36 kpathsea)
> tex4ht -f/foo.tex
>     -i~/tex4ht.dir/texmf/tex4ht/ht-fonts/
> (/usr/local/texlive/2015/texmf-dist/tex4ht/base/unix/tex4ht.env)
> (/usr/local/texlive/2015/texmf-dist/tex4ht/ht-fonts/iso8859/1/charset/unicode.4hf)
> (/usr/local/texlive/2015/texmf-dist/fonts/tfm/public/newtx/ntx-Regular-tlf-t1.tfm)
> --- warning --- Couldn't find font `ntx-Regular-tlf-t1.htf' (char codes: 0--255)
> ---------------------------------
>
> Complied using
> htlatex foo.tex
>
> Also tried make4ht and same result. Tried making math as SVG, no
> difference. the "fi" and "ff" are lost.
>
> specs: TL 2015
>> which htlatex
> /usr/local/texlive/2015/bin/i386-linux/htlatex
>
> thanks,
>
> --Nasser
>
>
>
>