This module was tested on 9th January 2019, using Drupal 8.6.4 with DX8 5.3.
There are known issues using the Workspaces with DX8.
You can only create new content that has a Layout Canvas on the default workspace (Live). Workspaces is currently experimental and there are known issues with Entity Reference Revisions.
Link to the module
Workspaces module is within Drupal Core.
Not working for you?
If this is not working for you, raise a ticket with our Customer Success team on our help center and we will look into your issue.