The Pirate Bay, a torrent website best known for sleazy sidebar ads, experimented with getting site visitors to mine the cryptocurrency Monero with their browser over the weekend—without their knowledge.
The mining was done as part of an experiment to replace The Pirate Bay's famously scummy ads, the site's administrators explained in a statement. Upon discovering the surreptitious mining, people were understandably upset: Cryptocurrency mining can slow down your computer.
Read More: At Least 1.65 Million Computers Are Mining Cryptocurrency for Hackers So Far This Year
Using website code to hijack computers in order to mine digital currencies like Bitcoin isn't new, but a popular site like The Pirate Bay springing it on users without telling them first is concerning. It's a fact now that at least one big website had no problem doing this, and there may be others who are surreptitiously experimenting with this nascent revenue model. The Pirate Bay used a tool called Coin Hive to hijack visitors' browsers, and it's not clear how many customers Coin Hive has. But it does indeed have customers. If you're already using an ad blocker to block banners, you sure as hell want to block in-browser cryptocurrency miners.
Thankfully, Scotland-based programmer Rafael Keramidas has got us all covered. On Saturday, he released a very simple Chrome extension called No Coin that blocks cryptocurrency miners on web pages. It works like an ad blocker and lets you disable or enable blacklisted URLs. Right now, that list only blocks Coin Hive products. And yes, you could simply add coin miner URLs to your existing ad blocker yourself, but that's work, and work sucks. You might also be the type of person who doesn't have a problem with ads but doesn't like the idea of a site using your computer to mine.
I tried No Coin myself and it seems to work as advertised. Coin Hive's landing page features a demo that uses your browser to mine cryptocurrency, and with No Coin enabled it would not work. As soon as I turned off No Coin, the miner started working and Chrome began eating up my CPU resources.
Honestly, it probably doesn't hurt to be a little proactive with this new, and kind of annoying, method of generating website revenue.
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