Let Firefox help you block cryptominers from your computer
Cryptocurrency miners may be using your computer’s resources to generate cryptocurrency without your consent. To evade the cost of power and computing resources, people (aka “cryptojackers”) deploy cryptominers to use your system’s computing capacity to do the calculations on your dime. If an unauthorized cryptominer is using your system resources to generate cryptocurrency you may notice things like your battery power draining quickly, your fan spinning (an indication that the computer is using more resources and generating heat) or your electricity bill going up.
Source: blog.mozilla.org