The labs team is happy to release Jetpack 0.2, which adds an experimental new UI element to Firefox as well as a number of useful APIs.

In the short few weeks since launch, we’ve already seen an amazing amount of generativity.

People have Jetpacks that do everything from extending the capabilities of the web to adding a Cylon to the browser; from taking snapshots of the current page to controlling music players. In fact, we’ve had over 40,000 downloads and over 40 Jetpacks (that we know about!) written by people who previously had only written for the Web. And Jetpack is still mainly a technology preview.

What’s New in 0.2?

Besides numerous bug fixes (including a particularly nasty one that would hide prevent extensions from being in the status bar), there are three main additions: slidebars, jetpack.future, and persistent storage.

Install it now.

Slidebars

Slidebars are a reinvention of the old sidebar feature of browsers. They allow quick access to a wide range of both temporary and permanent information at the side of your browser window.

Slidebars can be used for many things, like quick access to streams of information (like Twitter, Facebook, or Reddit), or for watching a video while you continue to browse the web.

Creating a slidebar is as simple as:

jetpack.slideBar.append({
  icon: "http://wikipedia.org/favicon.ico",
  url: "http://en.m.wikipedia.org/",
  width: 300
});

Which will create a slidebar which shows the mobile version of Wikipedia. You can read more about slidebars in the API documentation.

Slidebars are still experimental and have a lot of quirks. The API will change. That’s why they’re only accessible through a new feature…

jetpack.future

Jetpack is two things at once: it is a platform for experimentation and it is also a solid set of APIs that anyone to easily build new Firefox features. To enable Jetpack to be both stable and — at the same time — to experiment with not-quite-yet-ready features we’ve added the ability to import new features from the “future”.

Slidebars, for example, are still highly experimental. To use them, you need to import them from the future first.

Read more about future in the Jetpack enhancement proposal (JEP) for jetpack.future.

jetpack.future.import("slideBar")

This makes slidebars accessible from jetpack.slideBar.

Persistent Storage and Clipboard Support

One of the most requested features in the Jetpack development mailing list was for the ability to persistently store data across restarts.

We’ve added simple storage to the future module. The API is defined in the storage JEP. Using it as simple as:

jetpack.future.import("storage.simple");
var db = jetpack.storage.simple;
var data = {name: "Firefox", twitter: "@firefox"};
db.set( "friend", data );

Get Involved

Mozilla Labs is a virtual lab where people come together online to create, experiment and play with Web innovations for the public benefit. The Jetpack experiment is still in its infancy and just getting started. There are many ways to join the team and get involved:

• Install and play around with the initial Jetpack API and demos
• Write a JEP
• Report a bug
• Grab the source code and fix a bug or add a feature
• Discuss, debate and add to the design in the Jetpack discussion group
• Join us in #jetpack on irc.mozilla.org

— Atul Varma and Aza Raskin on behalf of the Jetpack development team.