Firefox Develops Protection Against Browser-Based Cryptocurrency Miners

Engineers at Firefox are working on methods to counteract browser-based cryptocurrency miners, which often have a highly negative impact on users’ experience while browsing the web. Firefox Product Manager Peter Dolanjski shared these development plans with Bleeping Computer following the recent publication of Firefox’s 2018 roadmap.

“Currently, Firefox Tracking Protection already blocks a number of popular mining scripts. We are exploring separate controls that will allow users to block unwanted scripts themselves,” Dolanjski noted.

Two Approaches to Blocking Browser Miners

Mozilla engineers are considering two main solutions to this problem. The first involves restricting the execution of JavaScript scripts in background tabs.

The alternative is to include miner protection in Firefox’s upcoming “ad filtering system,” which Mozilla plans to add to the browser in 2018 to protect users from unwanted ads.

Current Protection Features

At present, the system for blocking browser-based miners is part of Firefox Tracking Protection, which prevents Firefox from loading scripts from a specific list of sources. In its current form, this protection works through the Disconnect.me service, which blocks a range of domains associated with advertisers that secretly track user activity on websites. In November 2017, domains belonging to Coinhive and Crypto-Loot—companies offering browser-based cryptocurrency mining services—were added to the list.

However, this feature is not enabled by default and is only active when the user opens a private window. Firefox 57 users can enable protection by default, but the feature is not optimized for regular browsing, and most people will find it difficult to log in to most websites.