Firefox 35 Gets Performance Boost, Bug Fixes

The first Mozilla browser release of 2015 brings Firefox Marketplace and improved performance to desktop users.


Mozilla's open-source Firefox 35 Web browser became generally available on Jan. 13, providing users with new Web-based communication features and fixes for nine security advisories.

The Firefox Hello WebRTC (Web Real Time Communications) feature officially debuted in the Firefox 34 release in December 2014 and is now being enhanced with new capabilities. In Firefox 35, Mozilla has made it easier for users to connect to video calls. Users can now connect with each other by way of a unique URL that is shared in order to join a conversation.

Mozilla is also bringing its Firefox Marketplace to the desktop. The Firefox Marketplace is an app store for the Firefox browser, similar to Google's app store for its Chrome browser.

"Marketplace apps for Firefox desktop are specially optimized for a bigger screen," Mozilla's support page for Marketplace states. "These apps are made with Open Web technology, so you can run the same app on different operating systems and devices!"

As part of Firefox 35, Mozilla developers have taken several steps to improve performance. The new browser has improved image resizing performance thanks in part to a bug fix that turns on SSE (Streaming SIMD [Single Instruction Multiple Data] Extensions) support on x86 CPUs. Additionally, developers have added multiple capabilities that make the browser more responsive for handling dynamic styling changes. For Apple Mac OS X users, Firefox 35 now leverages tiled rendering that can also provide a performance boost.

Firefox 35 now supports the Cascading Style Sheets (CSS) Font Loading API, which can enable the dynamic loading of font resources in the browsers. Another new CSS feature supported in Firefox 35 is the CSS filter property.

"The CSS filter property provides for effects like blurring or color shifting on an element’s rendering before the element is displayed," Mozilla explains in its developer documentation. "Filters are commonly used to adjust the rendering of an image, a background, or a border."


Mozilla has provided nine security advisories as part of the Firefox 35 update, three of them rated as critical.

Among the critical advisories is MSFA-2015-01, which details memory safety issues in Firefox. There is also a critical security advisory for a read-after-free vulnerability in WebRTC, which is the underlying technology that enables the Firefox Hello communications feature.

The third critical advisory included with the Firefox 35 browser release is a media sandbox escape issue that impacts the Gecko Media Plugin (GMP).

"This bug would allow an attacker to escape or bypass the GMP sandbox if another exploitable bug is found in a GMP media plugin which allowed them to compromise the GMP process," Mozilla warned in its advisory.

Sean Michael Kerner is a senior editor at eWEEK and Follow him on Twitter @TechJournalist.

Sean Michael Kerner

Sean Michael Kerner

Sean Michael Kerner is an Internet consultant, strategist, and contributor to several leading IT business web sites.