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Firefox 4

At the end of January I released new versions of both the Web Developer and User Agent Switcher extensions. These patch releases primarily added support for the then upcoming release of Firefox 4 which eventually came out two months later. Since then I have been extremely busy at work and have not had much time to work on the extensions, but I wanted to give an update about some issues that were found with Firefox 4.

Web Developer

The main issue with the Web Developer extension in Firefox 4 is that the toolbar menus are not checked when they are activated on Mac OS X. This is actually an issue with Firefox 4 and I have filed a bug with Mozilla that they have acknowledged, but are still working on. Hopefully this will be fixed soon as it’s a major issue that affects all toolbar menus in the browser.

There are also a few features in the Web Developer extension itself that have issues in Firefox 4:

  • The toolbar display options always reset.
  • The ‘Mark All Links Unvisited/Visited’ features no longer work.
  • Wildcard cookies can no longer be added.

I’ll be looking to fix all of these issues in the next release of the Web Developer extension.

User Agent Switcher

The User Agent Switcher extension also has a couple of issues in Firefox 4. First of all, the extension is not easy to access in Firefox 4 on Windows. There are currently a couple of ways around this as explained in the screencast below and I’ll be looking to fix this in the next release.

The second issue is that Mozilla removed the ability to override some of the user agent properties in Firefox 4 that you could override in previous versions. Specifically the app code name and vendor and vendor sub properties can no longer be overridden. There is nothing I can do to workaround this, but I will be updating the User Agent Switcher extension to indicate that those properties have no effect in Firefox 4.


As always I cannot give estimates for when the extensions will be updated as it depends on how busy I am at work, but I am actively working on them whenever I have free time and will release them as soon as I can.

Web Developer 1.1.9 and User Agent Switcher 0.7.3

Patch releases of both the Web Developer and User Agent Switcher extensions have been released for Firefox. These releases primarily add support for Firefox 4 to both extensions as well as fixing a few issues in Web Developer including ‘View Style Information’ being vulnerable to a cross site scripting attack. The full list of changes to the Web Developer extension can be found in the release notes.

Web Developer 1.2

I had originally hoped to release version 1.2 of the Web Developer extension in time for Firefox 4. Version 1.2 will merge the Firefox and Chrome codebases of the extension, as well as adding new features and fixing a number of issues. However, this is still in development which is why I have released this minor update to make sure that Web Developer is at least compatible with Firefox 4.

I’m continuing to work on version 1.2 so look for progress updates on Twitter and Dribbble.

Web Developer 1.1.8 and User Agent Switcher 0.7.2

Updated patch releases for both the Web Developer and User Agent Switcher extensions have been released.

This version of the Web Developer extension fixes an issue where the ‘View Generated Source’ feature did not work, as well as combining the Firefox and Seamonkey versions of the extension into one build. The User Agent Switcher extension release should hopefully fix the problem with importing user agents in nested folders once and for all.

Apologies for the frequent updates, but hopefully these will be the final patch releases before the next major releases of the extensions.

Web Developer 1.1.7 and User Agent Switcher 0.7.1

Patch releases for both the Web Developer and User Agent Switcher extensions have been released. These releases add support for Firefox 3.5 to the Web Developer extension and fix some minor issues with the recent update to the User Agent Switcher extension—the full list of fixes can be found in the release notes.

Web Developer toolbar

User Agent Switcher 0.7

I have finally had the time to release a new version of the User Agent Switcher extension. The main changes in this release are the support for folders and separators in the user agent list as well as indicating a non-default user agent has been selected by more than just the icon color. The user agent list has also been updated to include both the Googlebot and the iPhone user agents. A full set of release notes is available.

User Agent Switcher toolbar