Multimedia macro with a video doesn't allow preview in JSD portal

Summary

If a KB article contains a video file, this will play fine in Confluence, but will not play back through the portal view of the customer but redirecting user to download it.

Steps to Reproduce

1. Create a page in a Confluence space that is linked as a KB
2. Add a short video to the page using the Multimedia Macro
3. View the article from the portal as a portal only user

Expected Results

Video should play fine in both Confluence and Jira SD

Actual Result

Clicking on the video download the file instead of previewing it.

Workaround

Use Widget macro on Confluence page