In an effort to increase the security of its extensions and themes galleries, Google announced today that it will be implementing some changes. It will charge developers a one-time $5 fee to list their extension and themes, and it’s also introducing a new domain verification system.

The fee “is intended to create better safeguards against fraudulent extensions in the gallery and limit the activity of malicious developer accounts” Chrome product manager Gregor Hochmuth wrote. The change will also apply to the upcoming Chrome Web Store for apps. Developers with extensions and themes already within the galleries (before 11am PST today) can continue to update them for free, but new developers will have to pay to contribute to Google’s ecosystem.

The new domain-verification feature allows developers to tie their extensions, themes, and apps with domains they own or manage with its Webmaster Tools. It will allow developers to better tie their products to their websites and brands, and users will be able to tell how official certain entries are.

The new developer fee is less about making money and more about making sure that spammers and hackers can’t easily sign up for multiple developer accounts.

Hochmuth reported that there are more than 6,000 Chrome extensions in the gallery, and that more than 10 million are downloaded every month. In comparison, Firefox currently has 13,255 extensions at the time of this post. But Firefox has had more than six years to build up its extension collection — Chrome only officially received extensions at the beginning of this year. Of course, developers were working on Chrome extensions for months before, but it’s still impressive growth for Google’s browser.