- Navigate to a URL manually, which results in an error (i.e. make a typo)
- Get the navigation error page
- Now open a new tab and start to type part of the wrong site name into the URL bar
- Notice there is a (prominent) suggestion for the wrong URL presented in the URL bar

Suggested resolution would be to not add URLs/pages resulting in a 4xx HTTP status code (or DNS resolution error) to the list of visited sites that feeds suggestions. Also likely don't add them to history - the page is logged in history with title "Failed to open page".