I swear by SwitchProxy for Firefox. I use proxies to test our work environment and route web traffic through a SSH tunnel when I’m on an untrusted wireless network. Unfortunately, SwitchProxy hasn’t been updated for some time – it doesn’t work on newer versions of Firefox.

I read this post which talked about tweaking .xpi files – the files mozilla uses for add-ons. Changing the extension from .xpi to .zip results in a file you can open with Windows Explorer. Open it up and look at the install.rdf file. There’s a line in the file that reads:

<em:id>{ec8030f7-c20a-464f-9b0e-13a3a9e97384}</em:id>
                <em:minVersion>0.8</em:minVersion>
                <em:maxVersion>2.0</em:maxVersion>

Change the lines to reflect your current version, update the file, change the name back to .xpi and you’re good to go.

This won’t work with all add-ons, as some of them require specific versions. SwitchProxy seems to work just fine, however.