Firefox Quantum, also called Firefox 57, has a new user interface that gives it a more modern look. More importantly, Firefox Quantum is built to be faster and easier to use, an effort that could help Mozilla scrape back users it lost to rivals Google Chrome and Apple’s Safari browser.

Firefox was one of the fastest growing Internet browsers in the late 2000s. But it lost momentum as Google Chrome, which is the leading U.S. browser on desktops, gained new users.

Mozilla released a test version of Firefox Quantum web browser in September in preparation for its upcoming official debut in November. Developers have been tinkering with the test version over the past several weeks to let Mozilla know if there are any bugs or security holes prior to Tuesday’s public release.

Speed is the big message that Mozilla is pushing with Firefox Quantum. The company says it brings massive performance improvements thanks to Project Quantum, the code name Mozilla used while building next-generation architecture for a new Firefox.

“Anyone who downloads this version, which is so advanced we call it “Firefox Quantum,” simply can’t help but notice the speed, performance improvements, and the responsively slick new UI,” wrote David Bryant in a Medium post Tuesday. Bryant is a fellow in Mozilla’s Emerging Technologies organization.

Firefox Quantum is capable of 66 runs per minute, that’s twice as fast as its previous version, according to Speedometer, a browser benchmark that measures the responsiveness of web applications. Mozilla says Firefox Quantum also uses 30% less memory than Google Chrome.

Here are a few details about Firefox Quantum that users might notice:

Google is the new default search provider in the United States and Canada.

The tab you’re on gets prioritized over all others

Private browsing mode

Performance improvements in the browser’s core

A new CSS engine called Stylo. Even if that’s getting too technical for you, this is what matters: Stylo is designed to take better advantage of hardware and for low power consumption.

Here’s a video that shows some of the changes.

[youtube https://www.youtube.com/watch?v=n6wiRyKkmKc?rel=0]

Mozilla has also integrated the popular app Pocket, lets people save web content for later readings and viewings, into the new Firefox Quantum. Mozilla acquired Read It Later, the startup that made Pocket, back in February. Recommendations from Pocket are now part of the new tab experience in Firefox Quantum. When users open a new tab in Firefox, they’ll now see three recommended stories from Pocket.