Fix older Firefox extensions/plugins to work in new Firefox

If you use Firefox (and if you're into web developement at all, you should be) you'll find out that at least during the beta/PR/RC releases, everytime you upgraded Firefox, it broke all your extensions.  At first you probably believe there was some change that broke compatibility, but I've come to discover that's not the case, it's actually much simplier than that.  Here are some steps I've found around the net (and rewrote) to fix older extensions so they work in Firefox 1.0 and newer

Older FireFox extensions do not work in newer FireFox not because of compatibility problems, but because the Extension's install metafile contains a minimum and maximum version number.  And currently developers are using the poor practice of putting Firefox's current version number as the last version the plugin/extension can work in.

To fix older plugins:

1. Extract the .XPI file into a folder (it's really a renamed .ZIP file)

2. Edit the install.rdf file with a text editor.

3. Somewhere around the 12th line or so you will find two XML tags that list the version numbers and they look like
        <em:minVersion>0.8</em:minVersion>
        <em:maxVersion>1.0</em:maxVersion>

4. Change the 2nd tag (maxVersion) higher than your current version, 1.9 is probably a great choice, but I'm sure 9.9 will work better in the long run.

5. You might want to slightly incriment the version number so you know this plugin has been changed, the tag for the plugin's version number is usually around line 8 and looks like
    <em:version>0.7</em:version>
   It's often best to just add another ".1" onto the version number (ex: 0.7.1) than to go up another notch like .8 since when the next version comes out, it will often be .8, and you don't want to confuse your fixed plugin with the new plugin.

5. Save the changes and zip up the package and simply rename it back to an .XPI file

6. Install the plugin.