Last week there was this girl, complaining to me that during her Mozilla Firefox 3.1 beta
update, she could not run her favorite Firefox add-ons anymore.
So I said: “Give it to me, I will fix this!”

The thing is that it was all so damn easy.
I ofcourse did not mention that to her cause she probably could have done this by herself.
But yeah, with that way of thinking you won’t score girls.
(I wonder if computer nerds can do so?)

Anyways, this is the way how you can change the allowed version for Firefox add-ons, so your new installed Firefox browser can handle the Firefox add-ons which are not allowed for your new version:

1. Download the Firefox extension (*.xpi) to your harddisk.
(Most of the times, you can download the Firefox add-ons from the developer websites)
2. *.xpi files are just archives and can be opened by for example WinRar (http://www.winrar.com). Extract it to your harddrive.
3. The structure should look like this:

[chrome]
[components]
[defaults]
[platform]
- chrome.manifest
- install.rdf
- license.txt

Open the install.rdf (resource description framework) file with your fav. editor. (it’s XML)
4. Change the maxVersion description line. For example when you are running under Firefox 3.1 Beta,
the plugin with max version 3.0.* should be highered up:

        <em:maxVersion>3.0.*</em:maxVersion>

To:

        <em:maxVersion>3.1.*</em:maxVersion>

5. Now save this file to your harddisk. Note that it makes no sense to directly edit this file in the archive, since the file won’t be saved.
6. Drag the edited install.rdf file in the xpi archive. This should overwrite the file and store it.
7. Last but not least; drag the changed xpi add-on, into your Firefox browser (add-on window). This should install the add-on without limitations.