A new version of Firefox available for download on Wednesday separates the browser into multiple separate computing processes, so that a rogue website that attempts to use up a lot of your computer's processing power won't drag down the websites in any other tabs you might have open at the same time.
Using multiple processes to handle demanding websites is nothing new: Chrome, Safari, and other browsers have already implemented the capability. Mozilla's delay, according to Firefox Head of Product Ryan Pollock, was related to ensuring compatibility for browser add-ons.
"While Mozilla's engineers knew that this new multi-process approach was possible, adapting Firefox to run in multiple processes would require breaking Firefox Add-Ons that depended on a single-process architecture," he wrote in a Medium post. "Mozilla was reluctant to do this because customizing Firefox through Add-Ons has always been very popular."
A switch from Firefox's proprietary add-on platform to cross-browser WebExtensions solved this issue, Pollock said.
Switching to multiple processes will not only improve performance for users who often open multiple tabs at once, but also for owners of budget PCs with little memory that may have trouble displaying even a single modern website. In fact, Mozilla claims that with the update, Firefox now uses less memory than Safari, Microsoft Edge, and the Windows, Mac, and Linux versions of Chrome.
On the other end of the spectrum, Firefox will now let PC users with lots of memory to spare customize the number of processes the browser uses, Pollock said. If your system has more than 8GB of RAM, you can enter "about:config" in your address bar to increase processes by adjusting the number for the "dom.ipc.processCount" setting.