Symptoms
When you share a Command Prompt or PowerShell window in Microsoft Skype for Business 2016 on Windows 10, version 1809 or a later version, the content of windows that are positioned in front of the shared window can be seen.
Cause
This issue occurs because Windows 10 changes a property on Command Prompt and PowerShell windows. This change causes the unshared windows not to be occluded.
Resolution
To fix this issue, install the May 4, 2021, update (KB4493155) for Microsoft Skype for Business 2016.