Google’s unfair performance advantage in Chrome:

This optimization can yield a nice performance boost for Google’s customers. Assuming the connection only requires a trivial amount of processing power and network bandwidth, of course. Setting up the connection early can be wasteful or slow down the loading of other pages if the user isn’t going to search the web.

There’s just one small catch: Chromium checks the default search engine setting, and only enables the feature when it’s set to Google Search. This preferential treatment means no other search engine can compete with Google Search on the time it takes to load search results. Every competitor must wait until the user has started to type a search query before Chrome will establish a connection.