tex4ht problem when creating gif files

i have small tex file for tex4ht. With the following call:

    htlatex test.tex 'html,gif'

it should generate test0x.gif, test1x.gif files and other
dvi/html files. I tested with tex4ht 2019 and the test file works as expected. With tex4ht 20200323, it creates only test0x.gif file and other
dvi/html files. The test1x.gif was not generated.

Does someone know why it’s only one test0x.gif file created with tex4ht 20200323.

Thank you so much!

My machine is running Fedora 33 and texlive 20200327.

It’s my test.tex:

documentclass{article}
usepackage{mathtools}
begin{document}
[ f(n) = left{
   begin{array}{l l}
             n/2 & quad text{if $n$ is even}
        -(n+1)/2 & quad text{if $n$ is odd}
   end{array} right.
]
[ 50 textrm{ apples} times 100 textbf{ apples} = textit{lots of
apples}^2 ]
end{document}