Mozilla yesterday announced the release of Firefox 54 web browser with new multi-process architecture that promises to make browsing with multiple tabs open faster and more stable, especially on computers with 8GB of memory or less.
With the latest release, Firefox uses up to four processes to run web page content across all open tabs. This means that a heavy, complex web page in one tab has a much lower impact on the responsiveness and speed of other tabs, according to Mozilla:
The old Firefox used a single process to run all the tabs in a browser. Modern browsers split the load into several independent processes. We named our project to split Firefox into multiple processes 'Electrolysis' (or E10s) after the chemical process that divides water into its core elements. E10s is the largest change to Firefox code in our history. Besides running faster and crashing less, E10S makes websites feel more smooth. Even busy pages, like Facebook newsfeeds, spool out smoothly and cleanly.
In Mozilla's own tests comparing memory usage for various browsers, it claimed that Firefox used significantly less RAM in macOS than both Safari and Chrome. The group has published an article on Medium explaining how the new E10s architecture works.
In one section titled "Why Chrome gets too hot when Firefox does not", Mozilla writes that Chrome's method of creating separate processes for each open tab can end up with each one consuming hundreds of megabytes of RAM, whereas Firefox reuses processes and content engines to limit memory usage.
By default, Firefox now creates up to 4 separate processes for web page content. So, your first 4 tabs each use those 4 processes, and additional tabs run using threads within those processes. Multiple tabs within a process share the browser engine that already exists in memory, instead of each creating their own.
Mozilla claims that Firefox's considerate memory usage means users with 8GB of memory or less can browse the web without the browser hogging resources, allowing them to do other things on their computer. Meanwhile, users with more than 8GB of RAM can bump up the number of content processes that Firefox uses to make it even faster.
To change the number of content processes Firefox uses, enter about:config in your address bar, and adjust the number for the dom.ipc.processCount setting (we'll be exposing a visible preference for this in an upcoming release).
Users can test out the claims by downloading Firefox 54 for free from the Mozilla website.
Mozilla has heralded the release of a new version of Firefox that it says enables resource-intensive web content like games, apps, and image-editors to run in a browser window at previously unachievable native speeds.
To accomplish the feat, Firefox 52 supports Web Assembly, a new standard developed by Mozilla, which it calls "a game changer for the web".
WebAssembly allows complex apps, like games, to run faster than ever before in a web browser. We expect that WebAssembly will enable applications that have historically been too complex to run fast in browsers – like immersive 3D video games, computer-aided design, video and image editing, and scientific visualization. We also expect that developers will use WebAssembly to speed up many existing web apps.
Mozilla has posted a video, embedded below, that demonstrates the WebAssembly standard and WebGL 2 in action, with the help of an 3D environment rendered in real-time using the Unreal 4 Engine.
In addition to Web Assembly, the update adds automatic detection of "captive portals" often used by hotel wifi networks that require the user to log in before they can access the web.
Mozilla has also built contextual alerts into input fields to warn users when they're prompted to enter username and password information on a page that isn't encrypted with HTTPS.
Other additions to this version of Firefox include CSS Grid, a Grid Inspector developer tool, and automatic disabling of plugins that use the Netscape Plugin API (NPAPI) besides Flash.
Mozilla and Tor have published browser updates to patch a critical Firefox vulnerability used to deanonymize users (via ArsTechnica).
The code execution flaw was reportedly already being exploited in the wild on Windows systems, but in an advisory published later on Wednesday, Tor officials warned that Mac users were vulnerable to the same hack.
"Even though there is currently, to the best of our knowledge, no similar exploit for OS X or Linux users available, the underlying bug affects those platforms as well. Thus we strongly recommend that all users apply the update to their Tor Browser immediately."
The exploit is capable of sending the user's IP and MAC address to an attacker-controlled server, and resembles "network investigative techniques" previously used by law-enforcement agencies to unmask Tor users, leading some in the developer community to speculate that the new exploit was developed by the FBI or another government agency and was somehow leaked. Mozilla security official Daniel Veditz stopped short of pointing the finger at the authorities, but underlined the perceived risks involved in attempts to sabotage online privacy.
"If this exploit was in fact developed and deployed by a government agency, the fact that it has been published and can now be used by anyone to attack Firefox users is a clear demonstration of how supposedly limited government hacking can become a threat to the broader Web."
The Firefox attack code first circulated on Tuesday on a Tor discussion list and was quickly confirmed as a zero-day exploit – the term given to vulnerabilities that are actively used in the wild before the developer has a patch in place.