Tralics converts LaTeX to xml, you can download it from their website or install it from the Debian repos. The last official release was in 2015 but it was modified in 2018. There’s a github page. I had some hopes for Tralics because it is mentioned on the MathJax FAQ page at the bottom.

Usage

tralics myfile.tex -noconfig -noentnames

will output a myfile.xml document. While there’s a list of supported LaTeX packages on their site some of them, amsthm for example, are marked “does nothing.” I modified the text file to define a proof environment (which stops it compiling to pdf) and to remove all the qedhere. There was some issue with an included jpg file too. There’s no support for hyperref and I just stripped out all the \href commands in the hope of getting some working output.

The xml file you get won’t render will in a browser even with -noentnames (without this it uses ∫ and so on which FF and chrome at least don’t like in xml files, though they will accept them in html). It seems like you’re supposed to use something like xsltproc to convert the xml output to html but I couldn’t find appropriate xsl style files or any example usage (although there are some examples of files converted to html that look good). This page from 2008 suggests the “extra files” on the Tralics site might be useful, but that seems to refer to an old version. I gave up at this point, it’s probably possible to get html conversion working but the sample outputs didn’t look any better than the best of the other methods I tried.