Web Browser Wednesday

You want to play on the bleeding edge of software so you go ahead and start testing Firefox builds. Maybe you are playing it a little safe and testing Firefox 2.0 or maybe you are pushing the limits and testing Firefox 3.0! Either way you are bound to run into some compatibility issues whether it be when installing extensions or when visiting sites.

I have previously put together a guide that became quite popular on how to test Firefox builds. The guide contained everything that I had learned up to that point, but I have learned some more since then.

Nightly Tester Tools

Extension compatibility is a major issue when testing Firefox builds. The Nightly Tester Tools extension is really amazing and will save you an unbelievable amount of time. It lets you force your Firefox extensions to become compatible with the version of Firefox you are running. When installing an extension, as pictured, there will be a checkbox that you can select which will allow the Nightly Tester Tools to make the extension compatible. Before Nightly Tester Tools came along you had to manually change the version numbers in each extension that you installed.

There are also some sites that check to make sure you are running a compatible browser before you are able to see the installation dialog box. The most notable site for this is Google. If you try and install the Google Toolbar in Firefox 2.0 you will get a dialog box that says “Google Toolbar requires Firefox 1.0 or later.” You can often get around these sites by simply viewing the page source for the site and searching the HTML code for “xpi”. The result should be the direct link to the Firefox extension and doing this for the Google Toolbar will result in You can do the same thing with Google Notebook and find the direct link to be

About:Config New

Hunting for those download links can be a little tedious at times and to make it easier you can change the User Agent. To do that you can either use the User Agent Switcher extension or you can follow these steps:

  1. Type about:config in the address bar of FireFox.
  2. Right-click and select New->String.
  3. Type general.useragent.override and press OK.
  4. Type Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv: Gecko/20060508 Firefox/ and press OK.
  5. You DO NOT have to restart Firefox for this setting to take effect.

Your Firefox browser will now be treated just like Firefox gets treated. If you wanted to choose a different browser then you can view this long list of User Agents that are available. You could also make Firefox pretend to be Internet Explorer but you may run into issues when viewing some sites.

Hopefully this will help you along as you run into compatibility issues when testing Firefox. Unfortunately there are some extensions that are truly incompatible with future Firefox versions and need to be debugged in order to work properly.