Converting the attached DOCX document to HTML, does not embedded the custom font.
image.png (20.9 KB)
The font was embedded into the DOCX file like this:
image.png (17.9 KB)
image.png (12.8 KB)
When converting the same file to PDF, the font looks correct.
GroupDocs.Viewer 23.1 was used for conversion with those options:
var options = HtmlViewOptions.ForEmbeddedResources("output_viewer{0}.html");
Please see the attached sample file with both conversion attached as well:
DOCX with embedded font to HTML.zip (1.4 MB)