What is Firefox Quantum?

Firefox Quantum (previously known as Firefox) is a free, open-source web browser created by Mozilla. In addition to being very light, the Quantum browser, written using the Rust programming language, launched with a variety of new features, including integrated pocket to save content on the fly, privacy enhancements like tracking protection, and two-click screenshots.

The overhaul didn't just make Firefox quicker and lighter on system resources, it also added a more modern, minimalist-style interface. Using the Photon design language, Mozilla's developers can produce an intuitive browsing experience that displays more web content.

Before the update, Firefox used to run everything in a single process. If a website or web page were loading poorly, the entire browser would perform sluggishly. It also meant if a tab crashed, the whole browser would crash.

However, with Firefox Quantum, you can control how many processes the browser runs; by default, Quantum uses four processes to view and render web content. Most modern computers come equipped with a multi-core CPU, so the default setting works well for the average user.

To change the maximum number of processes Firefox uses, though, follow the steps below:

In addition to being twice as fast as Firefox 52, Quantum uses less memory than Google Chrome. The image below shows the memory usage on the same system for Chrome and Firefox Quantum.

Running both browsers separately, with the same number of tabs/URLs open, yielded results close to the claims made by Mozilla.

The Mozilla development team has always placed a high level of importance on users' privacy. The release of Quantum introduced the option to enable Tracking Protection while browsing normally. Previously, this option was only available in Private Browsing mode.

Tracking Protection blocks online trackers from logging your browsing behavior and habits. When enabled, a few adverts or web tools may not load or function correctly, but overall browsing speed and fluidity will improve. The option to add Exceptions and Change Block List is available for greater customization.

To turn on Tracking Protection:

You can never have too many ways to grab a quick screenshot. Firefox Quantum has a built-in screen capture option accessible from the Page actions drop-down, on the right side of the address bar. You can use the crop tool to select a specific section of the page, grab the visible portion, or take a shot of the entire page.

Screen captures can be copied to the clipboard, saved locally, or uploaded to Firefox's cloud storage. To take a screen capture, open the vertical ellipsis menu on the far right side of the address bar, then select Take a Screenshot.

The option to restore previous browser sessions has been available for some time via the History menu. However, the feature to automatically restore your previous session on Windows startup was part of Firefox's 61.02 release. Although enabled by default, you can double check if session restore is turned on by doing the following: