after Bug 633390 landed, the url overlay is truncated in the middle the same way it was truncated in the address bar. however for the address bar it was suggested in Bug 596644 to truncate the host at start instead of the end to prevent phishing opportunities: "...the host portion is truncated at the end if it needs to be truncated at all. To help prevent phishing attacks, we should instead truncate it at the start so that subdomains are truncated. From Limi's bug 587908 comment 95: * For phishing reasons, we should also truncate subdomains when we run out of space, like this: http://www.friendly.reader.google.com.somephishingdomain.com/someverylongelementgoeshere becomes …somephishingdomain.com/…goeshere " this is still an issue with link at bottom overlay, when the window is small.