Back/Forward in SU 15

Just downloaded SU15. i find that the “Back/Forward” icon, that was so useful to me in SU 14, is missing from the toolbar. Can I get this back, please?

Would you mean the Undo / redo which is on the standard tool bar?

The fastest way to activate a toolbar is a right click in the empty space in the toolbar area.

I’m very much a noob, guys, thanks for the help!