Remove permanent redirect (HTTP 301) cache in Firefox

As a web developer configuring SSL certificates on websites you deliver, as we do, you might be faced, one day, with a small issue about configuring a 301 redirect from HTTP to HTTPS that has to be reverted. It so happens that browsers *really* take it to heart to cache an HTTP 301 (permanent redirect) message seriously and deeply. So much so that it might become very difficult to remove this redirect and ever be able to access the site in HTTP again.

Firefox 15 PDF Reader preview

In Ubuntu, the shipped Firefox 15 comes with the new embedded HTML5 PDF reader disabled. It is easy to enable though. Go to "about:config", search on "pdf" and switch the "pdfjs.disabled" entry to "false". Restart Firefox and test it pointing to some PDF URL. In case it does not work, have a look at the "Portable Document Format (PDF)" type to action association in "Edit->Preferences->Applications" and set it to the internal Firefox preview.

Enhance your usage of Firefox

When installing Ubuntu on one of the new machines we get from time to time, there's a common mechanism I repeat over and over with Firefox:
  1. install the Firebug extension
  2. install the Web Developer extension
  3. install the ShowIP extension
  4. install the GooglePreview extension
  5. change the link of the start bar icon to start Firefox, to "firefox -no-remote -ProfileManager %u" instead of "firefox %u"
The latest option allows you to launch Firefox using different profiles, each of them having its own extensions.

Java Applet Uploader bug in Gallery 2 + Firefox 3.0

This is a bug we've seen but have been unable to explain so far... for several people, all the Java-based Gallery 2 uploaders applets and apps are crashing the Firefox browser or putting it in an unstable state, preventing us from uploading pictures. Apache doesn't log anything wierd. The Java console isn't very eloquent (but it reports a few exceptions), but the browser doesn't get to show the applications that allow uploading files this way. There is, however, a solution, which is to have a *clean* Firefox getting to the uploader pages.

Geolocation in Firefox 3.5 and the outcomes for geocaches/cistes

Firefox 3.5 just came out and, within a bunch of improvements and new stuff, we can find a geolocation implementation. What's that? Che Hodgins explains that on his blog with an example. If I had to define it in a few words, my definition would be "it's a feature that makes it possible for a website to ask your location to your browser". Now, the thing is that, obviously, many new great cell-phones have both a GPS and a browser integrated. And this means...

HOWTO Install kana and kanji for Firefox on Debian Sarge

This article was first written in May 2004 for the BeezNest technical
website (
This is a quick manual on how to install kana and kanji (Japanese writing) handling for the Mozilla-Firefox browser (and probably all other browsers) on Debian Sarge. I don't know whether the following is or isn't mandatory, but these steps were enough to give a good result.

Installing the "Languages" extension

* Note: this section has proven useless so I have moved it to the end of t


This article was first written in December 2003 for
the BeezNest technical website (
Mozilla is the all-in-one open source Internet application suite. It features, among others:
  • a web browser: Mozilla Navigator,
  • a MUA: Mozilla Mail,
  • an HTML editor: Mozilla Composer,
  • a calendar manager: Mozilla Calendar
and is the engine of most other open source high-end web browsers available, on many platforms. It is derived from

Practical Firefox extensions for web development

This article is incomplete and was first written in December 2006
for the BeezNest technical website (
This is a small written note on the Firefox extensions that are practically very useful in our business and that should not be forgotten. Web Developer Very good extension adding a lot of testing features to your browser Firebug JavaScript console/debugger Snapper Allows you to take screenshots of what's going on in your browser Selenium IDE Allows you to capture a