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A Day With Mozilla

A month ago I found out that I had won a grand prize in the Extend Firefox contest and last week I met with Mozilla for a day of activities with the other winners: Michael Wu and Josep del Rio.


I started the day by taking Caltrain down to Mountain View where I met Michael and Josep as well as Rafael Ebron, Mozilla’s Product Manager. We headed to the Mozilla offices where Rafael gave me a quick tour before we had a bunch of publicity photos taken and met Alex Guerra from Mozilla’s public relations company A & R Partners.

Extend Firefox contest winners

After the photo shoot we drove back into the city to have lunch with Harry McCracken from PC World magazine. However, we arrived a little early and Rafael suggested we head to the Current TV offices where a friend of his could give us a tour.

Al Gore’s Office

Current TV is a national cable and satellite channel where a third of their programming is “viewer-created content”. They are located in the old E*Trade building in SOMA and we were shown their entire process including a studio, editing rooms and the main room where they control what is currently being broadcast. The office is stunning and the process is fascinating, plus we even were able to see Al Gore’s office as he is the Chairman of Current TV.

Al Gore's office

PC World & CNET

Following the Current TV tour we had lunch with Harry McCracken before meeting a number of people from, including Peter Butler and Jason Parker. We talked about and gave some demos of our extensions before Rafael showed sneak previews of some of the entries in the Firefox Flicks contest.

We still had some time to kill before dinner so we took Michael and Josep on a quick tour of the city as this was their first time to San Francisco. It was mainly a driving tour because of the rain, but we showed them North Beach, Coit Tower, Lombard Street, the Palace of Fine Arts and the Golden Gate Bridge. As we drove into the Presidio, Rafael called a friend and said he would try and see if he could set up one last tour for the day. His friend agreed and told us to meet him near the Yoda fountain…


So we headed into the lobby of the new Lucasfilm offices in the Presidio. Just in the lobby there were statues of Boba Fett and Darth Vader as well as lightsabers and award trophies. After signing in with security we began our tour.

Yoda fountain

First, we were shown the on-site cinema where they show movie previews to the company. Everything was designed to make the movie experience perfect, from sound-dampening walls to a state of the art digital projector. However, no food or drink is allowed inside in order to maintain the quality. From there we were led through high-tech security barriers to the main offices.

Han Solo

During the rest of the tour we saw editing rooms, dining halls, posters from every movie the company had worked on and countless models from movies such as Jurassic Park, Back To The Future and Ghostbusters constructed in incredible detail. A number of times we were told we could not go into certain rooms as they were working on current projects like Pirates Of The Caribbean: Dead Man’s Chest.

R2-D2 & Stormtrooper


After the amazing tour we headed to the Thirsty Bear for a quick dinner and met some San Francisco geeks including Steve Rubel.

All in all it was a fantastic day and I want to thank Alex and Rafael for their hospitality.

Chris Pederick


A month ago I posted about the Web Developer extension being chosen as a finalist in the Extend Firefox contest. Yesterday the winners were announced and I am delighted to say that Web Developer won a grand prize in the “Best Upgraded Extension” category.

My prize for winning is an Alienware Aurora 7500 Firefox Edition PC and a Firefox prize pack including a t-shirt, cap, and laptop bag. It was great to get nominated, so to win is just a bonus…but with those prizes, what a bonus! I am not sure how soon I will get the computer, but expect plenty of photos once it arrives.

Thanks to the judges who voted for me and to those of you who have helped to improve the extension by sending in bug reports and feature requests.

Chris Pederick

Mozilla Update

This weekend the Web Developer extension reached 1,000,000 downloads on Mozilla Update.

Chris Pederick

Extend Firefox

The Web Developer extension is a finalist in the Extend Firefox contest. The winners will be announced in mid-February and I am up against some stiff competition including IE Tab and Adblock. Wish me luck!

Chris Pederick

Web Developer 1.0.2

Version 1.0.2 of the Web Developer extension has been released. This is a patch release containing a few minor bug fixes.

Chris Pederick

Web Developer 1.0.1

Version 1.0.1 of the Web Developer extension has been released. This is a patch release containing a few minor bug fixes.

The localized build has also now been updated to the latest version. If you have already installed version 1.0 there should be no issues upgrading, but otherwise it is recommended to uninstall the previous version before upgrading.

Update: A couple of bugs have been discovered with the ‘Edit CSS’ feature so you may want to hold off on upgrading for the moment.

Update 2: The CSS bugs have been fixed and the extension has been replaced with the fixed version. I did not change the version number as the fix was minor, so if you have already installed this version you will need to re-install the extension.

Chris Pederick

Best Seats Ever

For Christmas I bought my friend Alex tickets to see the Los Angeles Lakers play basketball against the Golden State Warriors. However, instead of going with regular priced seats, I decided to splash out and bought tickets just a few rows back in the lower tier from StubHub. The game was this Saturday and it was awesome!

Golden State Warriors - January 2006

We were sat directly behind the sports reporters next to one of the baskets and, while I knew the tickets would be great, I did not realize how much they would change what you see of the game. Being that close to the action allows you to see and hear the players much more clearly and makes you really appreciate the physical nature of the game.


The game itself was fantastic—although the Warriors lost—with a number of ridiculous dunks from Kwame Brown, Baron Davis, Smush Parker and Jason Richardson. One of Jason Richardson’s dunks in particular was a breakaway where he appeared to be coming straight toward us in our seats.

While I certainly cannot afford to buy these tickets on a regular basis, I would love to do this again in the future.

Chris Pederick

Web Developer 1.0

A year in the making, I am pleased to finally announce the 1.0 release of the Web Developer extension. This release contains a huge number of new features and bug fixes.

Some new features to look out for are:

  • Display Element Information
  • Display Ruler
  • Edit HTML
  • View Document Size

Other notable new features are support for opening the current page in another application through the customizable ‘Tools’ menu and viewing the source in an external editor through the customizable ‘View Source’ menu.

Note: If you are upgrading from a previous version of the extension you are strongly recommended to uninstall the extension before upgrading. If you are having problems after upgrading you should uninstall the extension in safe mode and then re-install.

Chris Pederick

User Agent Switcher 0.6.8

Version 0.6.8 of the User Agent Switcher extension has been released. This is a minor update containing bug fixes and code optimizations.

Chris Pederick

Web Developer Beta 0.9.9

Web Developer Beta 0.9.9—a preview release of the next version of the Web Developer extension—is now publicly available. This release is for testing purposes only—for a fully supported version of the extension or localized builds please see the latest official release.

Note: If you are upgrading from a previous version it is strongly recommended that you uninstall the extension and restart the browser before installing the beta release.

Nearly a year in the making this release includes numerous new features and bug fixes. The list of new features is on the to-do list and the list of bug fixes is on the known issues page.

Known Issues

As a beta release this build is not guaranteed to be stable and does contain some known issues in addition to those listed on the known issues page:

  • File size features do not work with files that are not in the cache
  • Opening the page in another application does not work on Mac OS X
  • ‘View Frame Source’ does not work in Firefox 1.5

The idea behind this beta release is to give people the opportunity to provide feedback about this next version as well as report any bugs. Please report any feedback or bugs in the beta forum or via the contact form.

Chris Pederick

Does Web Developer Have Too Many Features?

I have read a few posts online recently that started to make wonder if the Web Developer extension has too many features and that this feature overload is reducing the usability of the extension.

What Started Me Wondering

First, Garrett Dimon posted Be Careful What You Wish For in which he says:

Knee jerk feature addition involves little to no deeper understanding and can be very harmful to the success of an application.

Then Jason Fried posted Forget Feature Requests and suggested this method for dealing with feature requests:

So, ask for requests, read the requests, listen to your customers, and then forgot what they said. Let them remind you over and over and over again. That’s how you find the real gaps in your product.

I found both of these posts interesting, but what really made me tie them back to the Web Developer extension was Roger Johansson’s post about Evaluating Web Sites For Accessibility With Firefox where he writes:

I regularly use the Web Developer Toolbar for evaluating accessibility, but I never realised some of the commands Patrick mentions existed. Outline Custom Elements, Linearize Page, and View Form Information are all very useful commands that I’ll be using a lot now that I’ve been made aware of them.

My Process

Feature requests for the Web Developer extension come in via either email or the forums and as long as I feel the request makes sense then it is added to the to-do list. I typically then work on the features that I consider to be the most useful or are getting the most requests, as well as any that can be implemented easily.

This is fairly unstructured and means I do not necessarily have a clear vision of what I am going to be including in the next release. Over time this has contributed to the menus becoming more cluttered and harder to navigate.

Extension Improvements

In version 0.8 of the extension the menus were tidied and I have repeated this exercise for the next release. In addition to adding menu separators, I have also replaced the alphabetical sorting of features with something hopefully more intuitive. Now the features under each category are grouped by behavior in the following order:

  1. Disable functionality.
  2. View functionality.
  3. Edit functionality.

The new CSS menu can be seen here, for example. As soon as I made this change I found the menus easier to navigate, although it will take a little time to get used to some of the new feature locations.

Web Developer

I think the biggest improvement that could be made would be to write some better documentation, but this is always a lower priority than development.


As much as anything this post is about soliciting feedback from users of the Web Developer extension.

Do you find the extension confusing and unintuitive? If you do, is this because of the menu layout or has the extension just become bloated with unnecessary features? Do you think some features should be removed from the extension and, if so, which ones? What other solutions would you suggest to make the extension more intuitive to use?

Chris Pederick

Internet Explorer Developer Toolbar

If imitation is the sincerest form of flattery then I am honored by the beta release of the Internet Explorer Developer Toolbar. While the AEVITA Web Inspector was a blatant rip-off, the IE Developer Toolbar, although clearly inspired by the Web Developer extension, is a separate and potentially useful tool.

The structure of the menus resembles the Web Developer extension with ‘Disable’, ‘Images’, ‘Misc’, ‘Outline’ and ‘Resize’ all being common between the two tools, as well as the ‘Validate’ menu correlating to the ‘Tools’ menu in the Web Developer extension. Most of the features have an equivalent in the Web Developer extension, although the IE Developer Toolbar contains fewer features – particularly those related to CSS.

Interesting Features

There are three unique features of the IE Developer Toolbar that stood out for me.

Firstly, ‘View DOM’ which is similar to the DOM Inspector in Firefox. What makes this feature unique is the option to ‘pin’ the DOM Explorer as part of the browser window which is useful.

Secondly, the ‘Show Ruler’ feature which gave Ben some ideas on how to improve the ‘Display Ruler’ feature that is part of the Web Developer Alpha.

Finally, the ‘Outline Positioned Objects’ feature which I have already added to the to-do list for the Web Developer extension and I am hoping to include in the next release.

A Promising Start

Overall, I think the IE Developer Toolbar is an interesting tool which, while clearly immature, shows some promise and it will be interesting to see how it improves going forward. For a more in-depth review of the IE Developer Toolbar with screenshots check out Cow’s Blog.

Chris Pederick

Web Developer 0.9.4

Version 0.9.4 of the Web Developer extension has been released. This release is purely to make the extension compatible with Firefox 1.5 Beta.

Chris Pederick

User Agent Switcher 0.6.7

Version 0.6.7 of the User Agent Switcher extension has been released. This release adds Netscape support and some code optimization as well as being compatible with Firefox 1.5 Beta.

Note: The Netscape support was not working and I am not really sure why, so I have removed it for now and will look to add the support back in for a future release.

Update: The localized version was not working correctly and has been updated with a new version.

Chris Pederick

Firefox 1.5 Beta Compatibility

This is really just a placeholder post for now as I am starting to receive emails and forum posts asking about Firefox 1.5 Beta compatibility for the User Agent Switcher and Web Developer extensions.

Update: The User Agent Switcher and Web Developer extensions are both now compatible with Firefox 1.5 Beta.

My usual stand is that I do not support nightly, alpha or beta builds for either extension—as noted in the User Agent Switcher and Web Developer FAQs. This is because too many little bugs appear in these builds that can affect the behavior of an extension and I just do not have the time to debug an issue to work out if it is a problem with that build or my extension.

However, with Firefox 1.5 Beta offering significant improvements over Firefox 1.0 I suspect that many people will be trying it out—myself included. Therefore I am planning on making both the User Agent Switcher and Web Developer extensions compatible with Firefox 1.5 Beta, with the caveat that I will not be providing any support for issues that are only related to Firefox 1.5 Beta and do not occur in Firefox 1.0.

Changes Required

Making the User Agent Switcher extension compatible should be straightforward enough and I hope to release version 0.6.7 this weekend. This will not include any new functionality, but will merely add Firefox 1.5 Beta and Netscape support along with some minor code optimization.

Unfortunately, the Web Developer extension is a little more tricky. I have spent the last few months working on the next release of the extension and version 0.9.3 is effectively frozen. If version 0.9.3 can be made compatible with Firefox 1.5 Beta by just updating the supported version then I will do that this weekend. Otherwise people will have to wait for the beta of the next release for a version of the Web Developer extension that is compatible with Firefox 1.5 Beta, which should not be too far away if everything goes according to plan.

So please stay tuned—I will be updating this post with the latest information as I work on making the User Agent Switcher and Web Developer extensions compatible with Firefox 1.5 Beta.

Chris Pederick

Web Developer Rip-Off

Someone sent me an email the other day with a link to the AEVITA Web Inspector. Web Inspector is described as “an add-on component for your Internet Explorer browser…for testing and optimizing HTML pages without complexity”. It sounds like an equivalent to the Web Developer extension only for Internet Explorer instead of Firefox, but a quick glance at it’s home page reveals it is more of a rip-off than an equivalent.


The first thing I noticed was that the icons used in Web Inspector are identical to those in Web Developer. These icons were not created by me, but are part of the default Firefox themes on Windows and Mac OS X, and I believe these icons are copyrighted by Mozilla.

Looking at one of the Web Inspector screenshots it was clear that not only had the icons been taken from Web Developer, but that the menus had an almost identical structure in terms of naming and order, with only a few items added and removed.

I also noticed that most of the text on the Web Inspector home page had been copied from the Web Developer documentation. For example, from the Web Developer documentation:

The disable features allow the disabling of various browser behaviors including disabling the cache, JavaScript and CSS.

And from the Web Inspector home page:

The disable features allow the disabling of various browser behaviors including disabling the cache, JavaScript and CSS.

What is particularly amusing about this is that the text was copied verbatim even though there is no feature that disables the cache in Web Inspector! The Web Inspector home page also claims that the program allows “an unlimited number of configurable tools” and “custom sizes” in the resize feature, but these are features of the Web Developer extension and are not included in Web Inspector.

I downloaded and installed the program and it behaves in almost exactly the same way as the Web Developer extension. This makes me suspect that much of the logic was probably taken from my code, although this is most likely hard to prove as I would guess that the internal code of an Internet Explorer add-on is very different to that of a Firefox extension.

No Response

I sent AEVITA support a polite email pointing out what appear to me to be clear violations of the GNU General Public License that the Web Developer extension is distributed under and the copyright of the Mozilla icons. At the time of writing I have yet to receive a response.

I find it sad that there are people who would abuse open source software in this way and even charge $24.95 for a license. This is certainly not about trying to stop any competition for the Web Developer extension—I have always been fully supportive of the Web Accessibility Toolbar.

I am not sure what my next steps will be, but I will post any follow-ups here.

Update: Asa Dotzler from Mozilla has picked up the story on his blog and is encouraging people to contact AEVITA and express disapproval.

Update 2: Web Inspector is also available from and ZDNet Downloads. Feel free to add your opinion to the user reviews of the tool.

Update 3: Davenport points out that Web Inspector appears to have been removed from the AEVITA web site.

Update 4: Audoin points out that the AEVITA web site is now simply showing a “Bandwidth Limit Exceeded” message.

Update 5: The AEVITA web site is back up again and all references to the Web Inspector have been removed, although James says that the images can still be accessed by URL. AEVITA have not contacted me, but I now consider this matter closed and want to thank everybody for their support.

Chris Pederick

Web Developer Alpha

Today I released an alpha version of the next release of the Web Developer extension to a select group of individuals to get their initial thoughts and bug reports.

Note: Before the comments and emails start coming in requesting to be a part of the alpha release—I am sorry, but I will not be releasing the alpha to any other people.

This alpha release contains most of the core functionality that will be included in the next release and the to-do list shows what has already been built. There are a few extra features that I want to include in the final release, but I am not looking to add in anything too major at this point.

Being an alpha release there are a few known issues—most notably unlimited customizable bookmarklets and ‘Validate Tided HTML’ not being complete—as well as almost certainly a number of bugs. The plan is to get feedback from this alpha release on the new features and any bug reports.

Release Plan

Once the necessary changes and fixes are made I will then be releasing a public beta for anyone to try—with the caveat that there will most likely still be some bugs, but hopefully nothing too major. Again bug reports and feedback will be incorporated before the final version is released.

As for the inevitable question around the timing of all of this—I cannot commit to dates as I only work on the extension in my free time and it really comes down to how busy I am.

So that is the latest news on the extension. Sorry if you wanted to try the alpha release, but hopefully the beta release will be available soon.

Chris Pederick

User Agent Switcher 0.6.6

Version 0.6.6 of the User Agent Switcher extension has been released. This is a patch release that fixes a bug where user agents containing backslashes did not work.

Chris Pederick

Mozilla Update Relaunched

Mozilla Update finally relaunched this weekend and the Developers Control Panel was turned on as part of this release.

This allows me to administrate my extensions and make sure that the information is current, so I have uploaded the latest versions of both the User Agent Switcher and Web Developer extensions. These updates still go into a moderation queue before appearing on the site, but hopefully that will only take a few days.

If you want the latest news about my extensions this site is still the best place to check out, but it will be nice to have the official extensions site up-to-date as well.

Chris Pederick

User Agent Switcher 0.6.5

Version 0.6.5 of the User Agent Switcher extension has been released. This release adds import and export support for the list of user agents and fixes a bug where user agents containing apostrophes did not work.

Chris Pederick