If you work on many projects, you probably have lots of workspaces. Over time, some of them become unnecessary. But they might be helpful again in the future. So you store them and things are getting messy.
The solution is to archive unused workspaces. You can unarchive them anytime you need.
To archive a workspace, open Workspace Editor and from the contextual menu (right click or ctrl click) choose Archive option.
Your workspace is moved to the archive. To open it, click on the Workspaces header over the workspace list and choose Archived. Now you can see all the archived workspaces. To unarchive one, similarly, choose Make active option from the contextual menu.