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The Chrome extension that hides your screen in plain sight

The Chrome extension obscures your web content under wavy lines and patterns, making it unreadable to anyone without red tinted glasses.

Imagine you’re sitting on an airplane, using webmail to send your marketing plan to your boss, when you notice that the passenger sitting next to you has wandering eyes.

Or you’re sitting in a crowded cafe, looking up information online about a medical condition.

Your seatmate might be spying on your company’s intellectual property, or a passerby might unintentionally discover something you really don’t want them to know, like your private health information.

This kind of data leakage is why some people use privacy shields to obscure their computer screens with a dark plastic film. But those privacy protectors aren’t perfect (they prevent reading from the side, but not from someone directly behind you).

Now there’s a Chrome browser extension called Decodelia that obscures your web content under wavy lines and patterns, making it unreadable to anyone without red tinted glasses:

A Chrome extension and glasses set that obscures your web content.

Freely browse without fear of judgement or loss of privacy from those around you.

DECODELIA renders your screen indiscernible without red tinted glasses.

Decodelia was created by Melanie Hoff, an artist and photographer interested in digital imagery and “social hacking.”

Hoff frequently works in public cafes in New York City, and recognized that privacy of information doesn’t just concern data sent over the internet, telling Motherboard:

There’s a lot of talk about privacy related tools and techniques that deal with our information that happens behind our screen, as in what we send out to the internet. And there isn’t that much interest or talk around the physicality of our screen – when we’re in public spaces people can see that.

Decodelia reveals the content of your browser only when you’re wearing red tinted glasses, similar to the way 3D glasses render clearly images that look blurry to the naked eye.

Hoff’s browser covers the screen with the same type of wavy patterns that banks use on the inside of envelopes to prevent snoops from reading your checks through the paper.

decodelia screenshot

So far, there aren’t a lot of Decodelia customers – just 20 people are using it, according to the Chrome Web Store.

However, one five-star review from user Dhruv Mehrotra hints at why Decodelia could become much more popular:

Not only has this application increased my productivity, it has reinvigorated my meager sex drive [by] allowing me watch my favorite nudie videos everywhere I go. Thanks MAH845, you are a hero.


Hahah, I look forward to reading the next article about charges being pressed against Dhruv Mehrotra for what he did in that subway car.

Quite an interesting approach…yet also the sort that makes you facepalm and lament “Drat…a simple idea I could’ve had but didn’t.”


Without having seen the app in action I speculate that moving video is far less affected by the obfuscation than static text… so I wonder if (and by how much) Dhruv may have overestimated the amount of privacy he actually has.


Bryan why n how would he overestimate when he can always cross check his privacy with naked eyes? wouldn’t he give ratings after thoroughly checking it, especially if he watches such obscene content? Common sense!


Per 007 and Maxwell Smart, 20th-century bleeding-edge espionage equipment consists of
– firearm that recognizes the agent’s palm print
– triple-encrypted radio implanted near the cochlea
– false tooth with bite-able cyanide capsule

21st century spy gear is solely
– Dr. Who’s old 3D glasses
– winking on the blue side


The trade-off is that instead of people behind you, the company that makes this extension can see everything you do online. I noticed when I tried the extension out the padlock was suddenly missing on my SSL/TLS encrypted sites. No thanks!


This plugin is a pretty good idea — unless your neighbor with wandering eyes also has red-tinted glasses.


It’s like those “hidden secret decoder glasses” from when I was a kid. My eyes see everything shifted to the blue part of the spectrum, so I’ve never had a problem seeing through the red obscuring patterns. Just a reminder that it’s not just those seeing things through rose coloured glasses who won’t need the decoder. Better than the privacy filter, but not a privacy panacea.


This would be great unless you’re surrounded by other privacy-conscious people, or privacy-busting crooks. They would be wearing the same glasses you are and it wouldn’t seem out of place when this gets widespread.


So it’s the same high-security encryption scheme that was used to keep Transformers tech specs a secret?


OK Everyone has the app and all the spies are looking through rose tinted glasses. What about those males who are colourblind? What “colour” glasses do they need to see the screen?


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