Firefox 95 is even more secure than Firefox 4, according to a new study by security experts at Mozilla. The study found that Firefox 95 is more resistant to attacks that exploit vulnerabilities in the browser’s software. These attacks can allow attackers to steal user data, crash the browser, or even execute malicious code. Mozilla has already released a security update for Firefox 95 that addresses these threats. The update is available now and can be downloaded from the Mozilla website.


Mozilla is getting ready to release Firefox 95. While the list of new features won’t exactly set the browser world on fire, the security upgrade the browser is receiving is nothing short of impressive The browser now includes a novel sandboxing technology called RLBox, which will significantly improve the security offered by the browser.

What is RLBox Sandboxing?

Basically, RLBox uses WebAssembly to isolate potentially-buggy code. The browser isolates five different modules called Graphite, Hunspell, Ogg, Expat, and Woff2. Mozilla says that it can treat these modules as untrusted code, which would prevent any vulnerabilities—even zero-days—from causing problems.

Many threat actors attack by chaining together two vulnerabilities. With RLBox, code can’t jump to unexpected parts of the rest of the program, and it can’t access memory outside of a specified region. Essentially, it’s contained, so threat actors can’t jump through multiple vulnerabilities to cause harm to your computer.

As for how it’ll benefit Firefox, Mozilla says, “RLBox is a big win for us on several fronts: it protects our users from accidental defects as well as supply-chain attacks, and it reduces the need for us to scramble when such issues are disclosed upstream.”

It doesn’t appear that Mozilla wants Firefox to be the only browser using this security process, as the company said, “Moreover, we hope to see this technology make its way into other browsers and software projects to make the ecosystem safer. RLBox is a standalone project that’s designed to be very modular and easy-to-use, and the team behind it would welcome other use-cases.”

What Else Is New in Firefox 95?

Firefox 95 also gets the ability to move the Picture-in-Picture toggle button to the opposite side of the video.

The browser also reduces the power usage of software decoded video on macOS, especially in fullscreen. If you use Firefox to watch videos on services like Netflix, you’ll find the power usage goes down a bit, which is a welcomed change.

While Firefox 95 doesn’t officially launch until December 7, 2021, you can download it through Mozilla’s FTP right now for Mac, Windows, and Linux.