When I convert PDF to XPS some bold fonts are lost

Question:

I have a PDF with some bold fonts, which are fully embedded in the PDF. When I convert to XPS these glyphs are no longer bold. What is happening?

Answer:

The software that generated the PDF is faking the bold font, by taking a normal font, and applying a stroke to it. While PDF format supports both filling and stroking a font, typically glyphs are only filled. Many formats, such as XPS and HTML, don’t support stroking text. This is why the font comes out looking like a regular font in the XPS.

We investigated some possible work arounds, but they caused more problems than they solved; such as a huge increase in file size, and corresponding performance drop.