Restore the process working directory ?

[jvenant]

I use subprocess in my firefox addon.
I'd like first to thank you for your work. It make my addon so much easier to develop and maintain.

I sent my addon to a full AMO validation and they said that :
"Since subprocess.jsm does not restore the process working directory after changing it to accommodate the workdir parameter, you must manually restore it when using it as such.".

So my questions are :

• Is restoring the working dir useful ?
• How to do a such thing ?
• Should subprocess do that by itself ?

Thanks again.