Firefox Addons...dopey question
 

So when I upgraded to a new computer one of my most valuable tools is now gone..a twitter add on in Firefox that hold unlimited accounts and with just a click you switch form one to the other. They don't support it anymore - no downloads for latest Firefox. The download i did find will not work.

I have it installed for years on a laptop with Win 7 and now he latest Firefox also and it works. I am a noob at what in "under the hood" when it comes to extensions, but does anyone know of you can just "copy files" from one PC to another and it will work?

ask the one who made it, there where you downloaded the plugin.

Won't work on the new firefox or won't install?

If it is saying it isn't compatible it can just be because of the version check thing rather than it never going to work.

Download the .xpi file that is the addon rather than installing it.

rename .xpi to .zip and unzip it. There is a file called install.rdf and inside that you need to change where it says <em:maxVersion>number</em:maxVersion> to <em:maxVersion>18.0.*</em:maxVersion> or whatever version you are trying to install it on.

zip everything up again. rename to .xpi and try installing it.