As with any other Firefox extension, installing FireGPG is a matter of a few clicks. However, since FireGPG relies on GnuPG, there are a couple of things you have to take care of in order to make FireGPG work properly. First, you have to make sure that GnuPG is installed on your system. You might also want to install a graphical front end to it -- for example, KGpg on (K)Ubuntu -- that you can use to manage keys. Finally, you have to generate the key pair required to encrypt and sign mails and text snippets.
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