SLAB only does specific workspace labelling. Let's remove B as a specific label and make it a global label. The Custom Menu turns on and B has disappeared as a label. The variable still exists however. WIX Go to the Custom Menu.
Global labels appear in all workspaces.
Note that you can make anything that can be put into a list a label. These remove the global label and the global object, which would otherwise remain when the specific workspaces are removed. The best way to learn is to create some more examples and play on your own. Learning 411 is easy if you take the time, and will reward you in time and organization savings many times over. As you learn the commands, you'll find that typing them in becomes easier then going to the custom menu.