In the former Gnome releases of Nautilus, I was used to use "backspace" to go up a directory.
When typing a name in a nautilus window, the visible items are narrowed
down to suitable names/folders.
After selecting wit the cursor keys and pressing <enter>, the directory is changed.
But I didn't know how to go one directory up with the keyboard. Now, I found a hint in an ubuntu forum.
The key's are <alt>-<cursor up/down/left/right>.
Something different, I have to become comfortable with, but it works.