What Your Browser Leaks About You

Every time you go online, you reveal more personal info than you realise. Robert Irvine explains how to identify and plug these leaks.

- Robert Irvine

What you’re doing right now

To get a feel for how you’re being watched online, visit Click (clickclickclick.click), a creepy but illuminating ‘experiment’ that gives you a running commentary of everything you do from the moment you visit.

This includes every click and movement of your mouse, the size and position of your browser window and the length of time you spend on and away from the site. The idea is that you unlock ‘achievements’ by performing different actions, as directed by a increasingly pushy voice (“turn on your webcam”), but Click also demonstrates how much info any website could potentially know about you. We tried browsing in private mode, disabling cookies and using a VPN and Click still kept watching us.

How to plug the leak 

The team behind Click says: “basically it’s all JavaScript, which is in the hands of every web developer today”. Indeed, the only way we managed to foil Click was to disable JavaScript: in Chrome, go to Settings, ‘Show advanced settings’, ‘Content settings’ and choose ‘Do not allow any site to run JavaScript’. In Firefox, type about:config into the address bar, press Enter and click ‘I accept the risk!’. Find the preference ‘javascript .enabled’ and double-click it to change its value to ‘false’. However, disabling JavaScript will stop many sites working properly, so it’s better to use an add-on such Quick Javascript Switcher for Chrome (bit.ly/quick416) or ToggleJS for Firefox (bit.ly/toggle416) to switch it on and off as required.