From the entry on Blackboard’s support site:
The main content area in the center of the screen and video areas in bottom left/right corners are not visible. Affected attendees will only see solid black…
Affected attendees will also be unable to hear others in the session. However, others will be able to hear and see them (if their microphone and camera are enabled).
The root cause is under investigation. Workarounds suggested by Blackboard include
- Try disabling the Send a “Do Not Track” request with your browsing traffic option in Chrome’s settings (see the article for more information)
- Use another supported browser.