If you have search suggestions enabled then "http:" will be sent. Firefox disables them in Private Browsing mode for this reason.
- https://support.mozilla.org/en-US/kb/search-suggestions-fire...
- https://support.mozilla.org/en-US/kb/search-suggestions-fire...
I guess I just had a different interpretation of "no requests are made to Google". It seems "no requests" was intended to be "no search suggestion requests" and not "no requests that leak this information to google".
What's the point of sending those characters?