Bug Rated 3 out of 5 stars
Here's a bug. Open a *new* tab. Press ctrl+l (or cmd+l for Mac) to enter the url field. Type 'ha'. Watch the 'ha' become replaced by 'wa'.
One workaround is to make sure every search engine has a non-empty keyword, even the default one. Then use that first, and follow up with the 'ha...' string so that it doesn't convert it to 'wa...' Of course the keyword can't start with 'ha'!