The Google Chrome Web Store has outlawed cryptocurrency mining extensions on the platform. They can no longer be uploaded, and extisting extensions will be delisted in due course.
The decision is explained by James Wagner, Extensions Platform Product Manager, in a blog post entitled "Protecting users from extension Cryptojacking ".
Wagner says that the platform has noted a marked increase in the number of extensions that have hidden cryptocurrency mining scripts in their code. These mine in the background, unbeknownst to the user. The word 'cryptojacking' refers to this activity.
The mining scripts are heavy on the computer, seriously affecting performance and power consuption:
The blog explains that cryptocurrency mining extensions had been allowed as long as mining was their sole purpose and they advertised themselves accurately. However this didn't happen very often: "Unfortunately, approximately 90% of all extensions with mining scripts that developers have attempted to upload to Chrome Web Store have failed to comply with these policies, and have been either rejected or removed from the store."
The decision to bar the extensions was effective from yesterday, and existing extensions will be removed by late June. Chrome Web Store will still allow extensions with "Blockchain -related purposes other than mining".
Cryptojacking is a growing problem worldwide. In December 2017 it was discovered that some popular streaming websites were making thousands of dollars by surreptitiously mining through their users' computers, and in February of this year thousands of websites in the US, UK, and Australia were infected by cryptojacking malware. These included government websites.
Google, to which Chrome belongs, recently banned all cryptocurrency advertising on its platform. In response, cryptocurrency advocacy organisations from a number of countries have begun the process of raising money to sue the media giant.