Mathematical character not rendered

[persep]

Hi, I have an epub file with a lot of mathematical symbols that are not rendered in SumatraPDF version 3.4.6-64 or 3.4.5-64 portable nor 3.5.15698-64. This is what I get, empty squares:

But with calibre 6.27 it's rendered ok

And with MuPDF 1.23.0 portable it also renders perfectly

I'm running Windows 10 64 22H2 Any options I should check?

[persep]

Yes but not publicly. Maybe I can send it by email?

[kjk]

@persep You can submit private test file as described at https://www.sumatrapdfreader.org/docs/How-to-submit-bug-reports

If it works in mupdf then it could be a font issue.

Note that @comalmot is not SumatraPDF developer so I'm not sure why he's asking you to send him the file.

[kjk]

BTW: after opening a file you can see logs with Ctrl + K Show logs command. It might provide some clue.

[persep]

The reason I didn't wanted to attach the epub file here is because it's a book I bought, nothing secret or confidential and I trusted @comalmot as a developer of SumatraPDF really deceiving that he isn't. I'd like to think he deleted the book. Serves me right for not double-checking who I send things

@kjk This is an extract of the log

ParseTranslationsTxt: 19181 lines, nStrings: 357
fonterror : invalid font version 75ee5e8b
fonterror : invalid font version 1f8b0808
couldn't find system font 'serif'
couldn't find system font 'serif'
couldn't find system font 'serif'
couldn't find system font 'serif'. 
...
couldn't find system font 'sans-serif'
couldn't find system font 'sans-serif'
couldn't find system font 'sans-serif'

There is a huge lot of the couldn't find system font 'serif' errors. And I've sent you the file and logs

[kjk]

For future reference: search for Definició 2.1.

Strangely it renders incorrectly but when I copy&paste, it shows correctly. So a font problem of some sort.