The support of OpenType fonts has been disabled on our document rendering servers due to a critical (and unaddressed) vulnerability with these types of fonts in Microsoft Windows.
Like in any other situation where a document refers to a font that cannot be rendered, a font substitution will happen.
If this change of rendering behavior is causing an unexpected effect, don’t hesitate to reach out to our customer support team.
For reference, Microsoft published the following advisory regarding this issue: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200006
The XMedius Cloud team.