Mozilla PrefBar

Rediscover Your Browser

Hendrik Weimer


Normal version

Cookies suck. But sadly, some sites require their visitors to accept cookies even for navigation purposes. Active content such as JavaScript, Java and Flash give similar headaches, as these components have often been a cause for security holes. Changing the preferences of your browser every time you visit such a site is a nightmare, but leaving everything enabled is also not the wisest option. At this point, the Mozilla PrefBar comes to the rescue.

As the name suggest, the PrefBar requires a browser of the Mozilla family (i.e. Firefox, Mozilla Suite or SeaMonkey). Installation is done using an XPI file, which means that a running browser is required. Performing a system-wide installation as root is possible, however updating the browser usually requires a re-installation of the PrefBar.

The PrefBar is a toolbar placed below the so-called Personal Toolbar. It consists of check boxes, drop down lists, buttons, links and a fancy separator. The elements of the toolbar can be changed by right-clicking on the PrefBar, leading to an easy-to-use configuration interface.

There are many functions available, most of them are represented in a check box allowing to enable or disable a certain feature of the browser. These include executing Java, JavaScript, Flash, accepting cookies and displaying cookie warnings, rendering images or popup windows and sending the referrer string to a site.

If you use your browser in different environments such as on a notebook at work and at home, it may be necessary to change the proxy settings. If you don't want to use different profiles, the PrefBar provides a drop down list to select the desired proxy host. Another case where this is useful is when you want to use an anonymous network such as Tor to access a single webpage.

Sometimes it may be useful to change the User-Agent string, which is how the browser calls itself when accessing a website. This can help if a site creator has designed a moronic browser switch, which bars users of specific browsers from viewing the site. And in other cases it may be quite interesting what happens if you pretend to be the Googlebo ...

Other features include the resizing of the browser window to predefined values and various buttons for opening a new browser tab, saving the page, deleting all stored cookies or clearing the cache. It is possible to add links to the PrefBar, however it is more convenient when using bookmarks for this. Local applications may be launched from the PrefBar as well, specific examples on how to do this are given.

In principle it is possible to add more features to the PrefBar, however the documentation is very brief on how to actually do this. If you want to add a new feature, all you have to know is the few magical JavaScript commands that perform the desired action in the Mozilla browsers. Unfortunately it is very difficult to find out these commands, and the PrefBar documentation gives no hint where to start looking.

In some aspects the PrefBar adds a new experience to surfing the web. It relieves the user from several problems everybody knows, especially when dealing with the products of incompetent web designers. Beyond that, the PrefBar offers some unique features and it will be interesting to see what will be added in future versions.

Got a question on Mozilla PrefBar? Post it as a comment!

Mozilla PrefBar
License:GPL/LGPL/MPL tri-license
Distributions: [?]□ Debian stable□ Debian unstable
□ Fedora□ Mandriva
□ Suse□ Ubuntu


  • Quick and easy browser customization
  • No documentation on writing extensions

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