Your computer mining cryptocurrency with hidden script ?

Nowadays cryptocurrency mining is become very popular many people are mining using their computer and building rig but this is new thread site owners are using mining cryptocurrency with your computer. Some times when you are browsing some sites and you heard your fan became noisy as hell you didn't even opening program that using your cpu.
Few days ago i was browsing some site and i heard my laptop became noisy so i opened my task manager and i saw my cpu is 100% and chrome is using it so i was like " wtf why chrome using my cpu this much" and i closed tab's 1 by 1 that is the one i first realized some site is using my cpu to mining.
here is the code

So i gathered some information about this script and it's called " cryptojacking"
It's secretly uses your laptop or mobile device to mine cryptocurrency when you visit an infected site.
The idea for cryptojacking coalesced in mid-September, when a company called Coinhive debuted a script that could start mining the cryptocurrency Monero when a webpage loaded. The Pirate Bay torrenting site quickly incorporated it to raise funds, and within weeks Coinhive copycats started cropping up. Hackers have even found ways to inject the scripts into websites like Politifact.com and Showtime, unbeknownst to the proprietors, mining money for themselves off of another site’s traffic.
Even some chrome extensions are using it so be careful when you download some chrome extensions.

How i find that script ?
Most of the time, the mining code are hidden in websites with banner ads, streaming video, and/or online games. This is because users tend to stay on such sites longer, providing a perfect cover for mining scripts that are adding burden to the host servers.
By checking the Internet source code, we can find the hidden code (Coinhive JavaScript Miner), which is based on a technique called CryptoNight Mining which is used to mine CryptoNote Cryptocurrency such as Monero, Dashcoin, DarkNetCoin, etc.

How to protect yourself from new Internet attack as this?

So as you see, cybercriminals no longer have to infect or hack your computer. Rather, through this type of online mining attack they can make easy money faster than before. As such, we expect to see this tactic used by more and more cybercriminals.
To protect yourself you could simply turn JavaScript off in your browser, yet that will likely diminish your online enjoyment. On the other hand, you can download and use the Opera browser, which blocks online ads for you.