Mozilla

Big changes to Firefox's "porn mode" -- the private-browsing feature that turns off recording cookies, history, and temporary files -- landed today in the Firefox Nightly build.

When it reaches the general public a few months from now in Firefox stable, the feature will allow you to run the private-browsing feature in a new window, without closing your regular instance of Firefox. This pulls the browser up to parity with Chrome, Internet Explorer, and Opera. Safari doesn't open private browsing into a separate window.

Firefox's project manager, Asa Dotzler, stated in the blog post announcing the changes that the update was no mere code change but took 19 months of planning because they "redesigned the existing private-browsing mode from scratch."

The changes will also allow you to open a link directly into private browsing, something that only Chrome can currently do.

Mozilla also announced today that the Firefox OS Simulator is ready for public use. The add-on installs into any desktop version of Firefox and will let developers test the apps they build for Firefox OS without having to install the operating system on a phone.