Export PDF Unable to Export Special Icon to PDF

How to Replicate The Bug

1. Install Zephyr add-on in JIRA as the provided of the "Special Icon"
2. Create an issue in JIRA with "Test" as the Issue Type. This issue type icon is provided by Zephyr
3. Add a JIRA Issues Macro in Confluence page
4. Ensure that "Issue Type" is one of the column displayed in "Display Option" field
5. Save the JIRA issue macro and the page
6. Export it to PDF

Expected Behaviour

Confluence should be able to render the special icon from Zephyr plugin into the pdf as rendered in the page below:

Resulted Behaviour

Unable to render the icon in pdf as can be seen in the attached pdf file.