Mozilla has announced on its blog the release of Firefox OS Simulator version 1.0, and the introduction of per-window private browsing in the Firefox Nightly channel.

As we previously detailed, the Firefox OS Simulator lets you play with Mozilla’s upcoming phone OS via a simple Firefox add-on. Since it launched just last month, a majority of today’s updates are simply bug fixes — that’s a good thing, as in our experience the simulator was unusable in some circumstances. Mozilla notes that Linux users in particular will benefit from this release, as it now runs on more Linux systems.

It’s noteworthy, however, that Mozilla is keeping the “Preview” status on the Simulator for now, as both the add-on and Firefox OS itself are in their early stages. You can try out the simulator here. After downloading, simply select “Firefox OS Simulator” from the Web Developer menu (Tools > Web Developer > Firefox OS Simulator) and click the “start” switch on the left. A separate application window will then pop up, and the OS will boot.

homescreen 2 Mozilla releases Firefox OS Simulator 1.0, introduces private browsing windows in Nightly build

Mozilla has also released a guide, in case you’re stuck:

As for the Firefox Nightly channel, Mozilla has added the ability to open private windows without having to quit your session. In other words, Nightly users can now run private and non-private windows simultaneously. In order to do this, right-click on any link and choose “Open Link in a New Private Window.”

Why would you need to do this? Here’s Firefox’s own example:

Say your Fiancée has been using Firefox and has several windows open that she wants to keep open, you can simply open a new private tab and she won’t know that you’ve been shopping for her engagement ring.

Private Browsing 730x549 Mozilla releases Firefox OS Simulator 1.0, introduces private browsing windows in Nightly build

So long as the feature tests well, per-window private browsing should make its way to an official Firefox release soon.

➤ Firefox Nightly & Firefox OS Simulator 1.0

Image credit: DPA / Getty Images