Google says Chrome isn't killing ad blockers

Google isn't trying to kill ad blockers. That's the message in a pair of Google blog posts published Wednesday in response to criticism of the search giant's plan to improve extensions in its Chrome web browser.

"We are not preventing the development of ad blockers or stopping users from blocking ads," said Devlin Cronin in a post on the Google Security Blog. "Instead, we want to help developers, including content blockers, write extensions in a way that protects users' privacy."

Google in October revealed a broad plan to improve Chrome extensions. In January, developers noticed that part of the plan, called Manifest v3, could hurt ad blockers. Manifest v3 is designed to improve Chrome extensions' performance, privacy and security, but one part of that change limits how extensions will be able to examine aspects of websites. Some developers have said this will torpedo their ad blocking and privacy extensions.

"There's been a lot of confusion and misconception around both the motivations and implications of this change, including speculation that these changes were designed to prevent or weaken ad blockers," said Google's Simeon Vincent in a post on the Chromium Blog. "This is absolutely not the goal."

Part of the debate concerns rules that ad blockers use to decide what to screen and what to display. Chrome's current design permits lots of those rules, so for example an ad blocker can check to see if elements on a website are coming from a very long list of ad-related internet addresses. The new approach had a proposed limit to those rules, a maximum of 30,000, which could've hobbled ad blockers and other extensions using those lists. 

On Wednesday, Google said that it's raising the limit to a global maximum of 150,000 rules. Last month, the search giant also said it plans an exemption for enterprise users.

Google stressed in its posts that Manifest v3 is still in development and that it'll work with developers. However, the company feels it's making the "right choice to enable users to limit the sensitive data they share with third parties while giving them the ability to curate their own browsing experience."

CNET's Stephen Shankland contributed to this report.

Originally published June 12, 10:59 a.m. PT.
Update, 11:46 a.m.: Adds more details on the planned changes to Chrome extensions.