# make4ht crashes, error code 256, when using arev with bold font

This might be known issue, but did not see it googling. I sort of remember seeing this before, but I could be wrong. So thought to post this just in case. If this is known, will delete this.

This MWE

\documentclass[11pt]{article}%
\usepackage{amsmath}
\usepackage{arev}

\begin{document}
\textbf{test}.
\end{document}


WHen compiled using make4ht --lua foo.tex causes

--- error --- Improper file favb8r.htf'
Make4ht: Fatal error. Command tex4ht returned exit code 256


Using TL 2017 in cygwin:

>ls -l /usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/alias/arev/favb8r.h
-rw-r--r-- 1 me None 44 Nov 25  2016   favb8r.htf

>cat /usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/alias/arev/favb8r.htf
.favb8r
htfcss: favb8r font-weight: bold;

>


May be the extra empty lines in the file favb8r.htf is the cause?

More complete console ouptput:

 .....
Output written on foo2.dvi (1 page, 10520 bytes).
Transcript written on foo2.log.
Make4ht: tex4ht  "foo2.dvi"
----------------------------
tex4ht.c (2012-07-25-19:36 kpathsea)
tex4ht foo2.dvi
(/usr/local/texlive/2017/texmf-dist/tex4ht/base/unix/tex4ht.env)
(/usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/iso8859/1/charset/unicode.4hf)
(/usr/local/texlive/2017/texmf-dist/fonts/tfm/public/arev/favb8r.tfm)
(/usr/local/texlive/2017/texmf-dist/tex4ht/ht-fonts/alias/arev/favb8r.htf)
--- error --- Improper file favb8r.htf'
Make4ht: Fatal error. Command tex4ht returned exit code 256


The error do not show up when using make4ht foo.tex. Only when adding --lua does the error show up.

There is a bug in the configuration file for favb8r font, favb8r.htf, it references to itself:

.favb8r
htfcss: favb8r font-weight: bold;


it should be

.favr8r
htfcss: favb8r font-weight: bold;


The first line after dot references to another .htf file that contains definitions for each character provided by the font, the second line contains CSS definitions for bold face.

I've found more serious bug though, the resulting HTML don't contain spaces. See this sample file:

\documentclass[11pt]{article}%
\usepackage{amsmath}
\usepackage{arev}

\begin{document}
\textbf{test, space}, test, \textit{text} text with spaces
\end{document}


It results in:

which isn't really good. It seems that tex4ht cannot detect spaces in the DVI file. I don't know the solution at the moment.