How can I create a .jar file from a folder that contains a Firefox skin in it? I figured how to extract it, but retracting is a bit of a problem.

add all into a .zip file then change the extension to .jar

I forget how to change the extension, can you tell me how?

Make sure you have "show file extensions for known file type" turned on, and just rename it.

Another way to do it is import the project into eclipse and export it to a jar. That way, it can also be executable.