Mozilla on Wednesday released Firefox 53 for Windows, Mac, Linux and Android. Chief among the changes in Mozilla’s latest is the inclusion of a new Quantum Compositor, a couple of new themes for desktop users and the drop of support for older versions of Windows.

Originally announced in October, Project Quantum is Mozilla’s effort to develop a next-gen browser engine to take full advantage of modern hardware. The Quantum Compositor is one of the first important pieces of the puzzle. As Mozilla’s Nick Nguyen explains:

We’ve now extracted a core part of our browser engine (the graphics compositor) to run in a process separate from the main Firefox process. The compositor determines what you see on your screen by flattening into one image all the layers of graphics that the browser computes, kind of like how Photoshop combines layers.

Because the Quantum Compositor runs on the GPU instead of the CPU, it’s super-fast. And, because of occasional bugs in underlying device drivers, the graphics compositor can sometimes crash. By running the Quantum Compositor in a separate process, if it crashes, it won’t bring down all of Firefox, or even your current tab.

In testing, Mozilla claims the Quantum Compositor reduces browser crashes by about 10 percent.

Firefox 53 for desktop also ships with two new themes – Compact Light and Compact Dark – that shrink the size of the browser’s user interface in order to provide more real estate for web pages. Compact Light retains Firefox's default light color scheme while Compact Dark inverts colors to reduce eye strain (especially in low-light environments). To toggle the new themes, simply click the menu button then select Add-ons -> Appearance.

Mozilla’s latest officially drops support for Windows XP and Vista (32-bit Mac OS X is no longer supported, either). Microsoft, if you recall, ended mainstream support for Windows XP in 2009 while Vista reached end-of-life status earlier this month.