Use case or problem
I mainly use workspaces for different uni modules, and with so many folders in my setup, having the corresponding/related folders for different modules open while switching would be very useful instead of having to open/close relevant folders every time I want to revise a different module. The same can be said for various items in the sidebar that I may (not) want open for a given workspace.
Proposed solution
Allow Workspaces to remember the folders open in the sidebar as well as any other items (including their positions) within the sidebar.