My favorite feature of Firefox is its ability willingness to be customized into anything I want through third party add-ons and the built-in user interface customization tool. Firefox 4’s main UI is a big change from Firefox 3, and as it gets very close to release, I see many people asking how to change things back to what they had before.

This post walks through how to customize Firefox’s UI to look like Firefox 3, though I ask one thing of everyone reading it: please give the new defaults a chance. They aren’t right for everyone, but a lot of time and research went into how people use Firefox and I think they’re a step in the right direction. I’m making this post because I’d rather see people using Firefox 4 with a few older UI elements than using Firefox 3 and missing out on all the other awesome improvements because of one UI irritation.

Comparison of Firefox 3.6 and Firefox 4 default UIs

Add-on-Con party chalk boardLast Wednesday and Thursday I spoke for the third year at Add-on-Con. This year’s conference was notably different from the rest for a number of reasons, the biggest being a focus on apps. It certainly gave me a lot to think about, and hopefully I’ll have time to blog some of my thoughts on the topic of add-ons vs. apps.

Wednesday night’s Mozilla Social was a blast, so thanks to everyone who attended! And a huge thanks to the many people at Mozilla who were involved in our participation at Add-on-Con this year: Grace, Sara, Mayumi, Dan, Caitlin, William, Mary, Jane, and of course to our speakers Myk, Mark, Jorge, Boriss, Dave, and Jay.

Many people have already asked for my slides from my various talks, so here they are:

So much has changed since the last Add-on-Con and 2011 is already promising to be a very exciting time for add-ons, so I can only imagine what themes will surface at next year’s conference.

This Wednesday and Thursday, the Computer History Museum in Mountain View will be overrun with add-on developers eager to learn, collaborate, and network at this year’s Add-on-Con. I’ll be speaking at a number of sessions for the third year, and am looking forward to seeing familiar faces and first-time attendees.

If you’ll be attending (or even if you aren’t), be sure to join us after the first day’s training sessions for the Mozilla social from 5 – 9pm. Learn more and RSVP here.

This morning I pushed out my fifth blog theme, fligstripe. For Firefox and Webkit users, it’s 100% CSS using overlayed gradients. For Opera and IE users, it’s 100% screenshots of what it would look like if their browser supported CSS3 gradients.

I was going for a really clean design, which meant removing things like category navigation, tag clouds, and even the search box. I’m also using a few new third-party plugins and libraries:

I have a good feeling about this theme and hope it will last at least a year before I start to dislike it, as my previous 2 themes have only lasted a few months.

Back in March I blogged about an idea to make the Get Add-ons pane of the Add-ons Manager in Firefox 4 remotely hosted and much-improved. It would help users learn about and discover new add-ons through fresh content and recommendations. This afternoon we launched something extremely close to that:

screenshot of Discovery Pane