Use case:

1. Hit ctrl+t to go to a new tab.
2. Hit ctrl+L to get to the location entry.
3. Type 'search term' and then hit enter.
4. A dialog will pop up that says "The URL is not valid and cannot be loaded."
5. As this happens that search term is deleted from the location entry (or if a different page was loaded the URL of that other page returns).
6. I want to go back to the location entry but use my search term with a smart bookmark but it has already been deleted.

Epiphany appears to put the previous URL back in the location entry if the typed URL is invalid. I consider this bad behavior as the user is probably still interested in the URL he/she previous typed even if it was invalid. Strangely enough, if I go to a different tab and then back to the tab I typed 'search term' in the search term is back. This coming back feature is there whether or not the page was originally blank.

I propose the location entry not be immediately deleted unless the text entered was successful. The user may press 'Esc' if he/she wishes to bring the old URL back.