Mozilla today made two announcements that should make hardcore Firefox users very happy. The first is that multi-process support is landing in Firefox Nightly, and the second is that 64-bit Firefox is finally coming to Windows.

The features are a big deal on their own, but together they show Mozilla’s commitment to the desktop version of Firefox as they both improve performance and security. The news is part of a slew of unveilings from the company on the browser’s 10th anniversary — including new Firefox features landing today and the debut of Firefox Developer Edition.

Multi-process support

Mozilla has been building multi-process support as part of a project called Electrolysis for many months. Work to make the frontend and addons support multiple processes began in early 2013.

Here’s the goal outlined on the wiki page:

The goal of the Electrolysis project (“e10s” for short) is to run web content in a separate process from Firefox itself. The two major advantages of this model are security and performance. Security would improve because the content processes could be sandboxed (although sandboxing the content processes is a separate project from Electrolysis). Performance would improve because the browser UI would not be affected by poor performance of content code (be it layout or JavaScript).

Also, content processes could be isolated from each other, which would have similar security and performance benefits. Although the Gecko platform supports multiple processes, the Firefox frontend is not designed to use them.

Electrolysis has seen multiple delays, and the fact that it has landed in the Nightly channel today is a big relief for those wondering if the feature would ever make it to Firefox. While Mozilla didn’t share a timeline for when the feature will get past the Nightly channel, its arrival means it will be released for all eventually.

For context, Firefox development starts with Nightly builds, which consist of the latest Firefox code packaged up every night for bleeding-edge testers. It is then followed by the Firefox Developer Edition (or Aurora on mobile), which includes everything that is labeled “experimental.” After that, the code eventually finds its way to Beta and then finally Release for the broader public.

64-bit Firefox for Windows

Nightly builds of 64-bit Firefox for Windows have been available for years, but the feature never have made it past the first channel. In November 2012, Mozilla quietly killed off 64-bit Firefox, only to reverse the decision a month later after massive backlash from users.

Now, Mozilla is singing yet another tune. Mozilla Chief Technology Officer Andreas Gal is promising his company will ship 64-bit builds of Firefox to Windows “soon.” Until then, Windows 64-bit users can use 32-bit or 64-bit versions of Internet Explorer, Chrome, or Opera.

Mozilla already offers 64-bit Firefox for Mac OS X, but a Windows version will be a welcome addition. Gal didn’t mention anything about a Linux release, though 64-bit builds are unofficially available on the company’s FTP server.