The OP is using the word "tab" loosely. He means that it is opening in its own entirety.
For example, if I click "Boot", I get this

Click image for larger version

.If I then click one of the sub folders, it moves on in the same way. The root folder seems to have disappeared. As in the OP's case, there does not appear to be an option to continue to show the previous root folders. I don't have one to hand, but I recall that in Windows 7, a new window opened, but the previous window was still open for examination?

P.S. Brummyfan. The suggestion does not make the change.