Here’s an online privacy vulnerability you may face every day but have probably never thought about much: the autocomplete feature in your Web browser. Keep reading to learn why autocomplete is a privacy risk and how to disable it.
Autocomplete is the feature that makes suggestions about search terms as soon as you begin typing them in Google, Bing, Yahoo! and other search enginges. Generally speaking, it’s not the biggest privacy hole in your system.
Still, autocomplete could leak information about you in various ways. For one, since the search page you use may not be encrypted via HTTPS, someone eavesdropping on the network could potentially monitor your keystrokes as you type.
They could also monitor your complete search terms under these circumstances, of course. But reading your search queries as you enter them raises even greater privacy flags because it provides information about things you might be interested in, even if you stop short of performing a complete search.
In a similar way, a search engine company could use information from autocomplete to make predictions about your interests or online behavior whether or not you actually enter a full search term. If you start typing “how to cheat on t” but think better of it before entering “es” and pressing enter, the search company could assume that you’re interested in information related to cheating on taxes.
Search companies provide few public disclosures regarding what they do with data they collect from autocomplete, so they could use it to identify you or serve you ads. They could also potentially share it with government authorities without telling you.
By the way, even if you are not logged in to your Google, Microsoft or Yahoo! account when using one of those search engines, other identifying information – like your IP address or cookies in the browser – could be used to link you to search information you enter. That means that browsing anonymously does not necessary circumvent the privacy issues associated with autocomplete.
In general, you’re best off using a search engine that does not track you at all, like StartPage or lxquick. But if you choose to use one of the major commercial search engines, you can gain a little extra privacy by disabling autocomplete. To do so, open the about:config interface in Firefox (by typing “about:config” in your search bar), find the “browser.urlbar.autoFill” entry and set the value to “false.”