Screenshot by Dara Kerr/CNET

It appears Google is true to its word.

One month after the company announced that it was kicking some toolbars and other "multipurpose extensions" out of the Chrome Web Store -- to keep its browser's interface uncluttered and to protect users from unpleasant surprises -- it has removed two Chrome extensions, according to The Wall Street Journal.

The two extensions, "Add to Feedly" and "Tweet This Page," reportedly had their code updated so that users would see more pop-up ads while using Chrome. Dozens of users took to message boards after the update to complain about the ads.

Google is said to have removed the extensions because they violated its terms of service, according to The Wall Street Journal.

The Web giant generally favors open app stores that are governed more by user reviews than by a central authority approving software. But even with its relatively open approach, Google is still showing it has an ecosystem it wants to govern. In its policy change last month on toolbars and other "multipurpose extensions," Google said that extensions should have "a single purpose that is clear to users."

"Do not create an extension that requires users to accept bundles of unrelated functionality, such as an email notifier and a news headline aggregator. If two pieces of functionality are clearly separate, they should be put into two different extensions, and users should have the ability to install and uninstall them separately," Google wrote in its updated Chrome Web Store developer policies. "For example, functionality that displays product ratings and reviews, but also injects ads into web pages, should not be bundled into a single extension."

The developers for both "Add to Feedly" and "Tweet This Page" were reportedly paid to alter their code, according to The Wall Street Journal.

Amit Agrawal, developer of the "Feedly" extension, penned a blog post on Thursday saying that he sold his extension but now regrets it. Once Feedly got in the hands of the new owner, it became laden with "invisible ads that work the background and replace links on every website that you visit into affiliate links."

"No surprises, the ratings of the extension have recently plummeted at the Chrome store but the business model of the buyer is simple -- they buy popular add-ons, inject affiliate links and the bulk of users would never notice this since the Chrome browser automatically updates add-ons in the background," Agrawal wrote. "And there are no changelogs either."

The practice of extension developers being offered payment to include ad code appears to be increasing. According to The Wall Street Journal, several popular extension developers have said they've been offered money to add advertising code to their extensions. While receiving money to include ad code isn't against Google's rules, developers still must comply with the company's extension policies of having one functionality.

CNET contacted Google for comment. We'll update the story when we get more information.