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0 pointsamjd12y ago0 comments

It's a neat little hack to predict your interests among various categories.

The hundreds of grey boxes that you see are actually links to sites belonging to different categories like programming, science etc. and the red ones are those that you have visited (based on your browser history). The basic idea here is of using the CSS selector a:visited to highlight visited links in red, and by clicking the red boxes the users themselves reveal the sites they have visited. The website then uses this information to draw a pretty pie chart showing which categories the user is interested in.

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4 comments · 2 top-level

xmonkee12y ago· 2 in thread

Apart from making it seem like a game, is there any reason why the user has to click the squares? Is there a way for the browser to report back which elements are currently red?

_delirium12y ago

That used to be possible by reading the styling in JS, but that was considered a privacy bug, since any website could slurp information from your browser history. Therefore there was an overhaul of what kind of styling could be done based on history, and what could be read back about it in JS: https://blog.mozilla.org/security/2010/03/31/plugging-the-cs...

dalke12y ago

No. Or rather, there isn't supposed to be. About 8 years ago (see http://jeremiahgrossman.blogspot.com/2006/08/i-know-where-yo... for an early demonstration) it was possible. This was considered bad, because it could help malicious sites gain information about the browser history which might help with an attack.

The browser developers responded by minimizing what a ":visited" can do, so Javascript shouldn't be able to get direct, or indirect through CSS, access to that information.

danielweber12y ago

I thought it was going going to be a psychological experiment in how patient I was in clicking the little boxes.

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