February 7, 2008

Making Firefox 2.0.0* extensions work in Firefox 3.0.2*

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Richard Lee @ 11:10 am

I downloaded Firefox 3 beta 2 today. Give it a whirl i thought. But of course my beloved Web Developer and View Source Chart extensions were disabled because of incompatibility. I was almost about to revert back to 2, but being the stubborn person I am sometimes, I didn’t believe it so I did a bit of Googling and low and behold i stumbled upon some discussion on Mozilla about making the Greasemonkey add-on work under the new Firefox 3 beta - and it turns out all you need to do is hack the installation manifest to change the version compatibility . To summarize here’s what you need do :

  1. Download the xpi file of your plugin by right-clicking on the Install Now button and selecting Save Link As
  2. Right-click the downloaded my-extension-blah.xpi file and using 7-Zip select Open Archive (.
  3. Navigate to the install.rdf file and right-click and select Edit and find the maxVersion tag and change 2.0.0.* to 3.0.2.*
  4. Save your install.rdf file and close. Z-Zip will prompt if you want to update the archive so make sure you press ‘Yes’
  5. Finally open the file in Firefox, or drag it into a blank tab and the installation procedure begins as per normal.

Note: Please note i could only extract the and update the xpi package with 7-Zip, other zip programs didn’t repackage the xpi file properly, i kept getting errors when installing the package.