When typing a URL orion should guess and show a complete URL that can then be opend via pressing the open-button.
At the moment orion only shows suggestions from history in a list below the adress field, but does not show suggestions in the field itself. In Safari one can type "ama" and the auto suggestion would show "amazon.com". Hitting the open-key on the keyboard would open amazon.com.
This is what it looks like on orion:
This is the how it's in Safari: