Personally, I'm not a fan of Norton Internet Security. This is my least favorite of Norton's products. If it is telling you that your Foxfire is recording keystrokes and mouse clicks, you might want to check where those keystrokes and mouseclicks are going - certainly not to Mozilla. My guess is that you either downloaded yur Foxfire from a site with what we refer to as a "dirty copy", or that you picked up some malware along the way.
In addition, you have to remember that Norton is NOT free and I've seen & heard of many people with Norton IS telling them their antispyware programs have spyware (and other companies have set their anti-spy-ware to show that other anti-spy-ware companies' software contains or is spyware.)
If it were me, I'd ditch Norton IS and buy a better antivirus program & use respectable anti-spy-ware programs, find where the supposed or real addition to Foxfire is located manually and get rid of that, as Mozilla's Foxfire is open-source for a reason, so you can edit it, put add-ons for what you use, etc. Aparently you MAY have picked up a bad add-on, or worse downloaded a dirty copy from a non-mozilla site (and there are some that exist!) My Mozilla and everyone I know's is fine!
I know of one person that bought Norton IS and came up with supposedly all kinds of spyware, etc. (most of which is freeware), and it seems that they don't like freeware competing with them, so this person (very unwisely) got rid of the good antispyware programs they had, and are now totally relying on Norton to keep them safe from everything. Needless to say, I doubt I will EVER work on their computer again. I have NO desire to and politely told the owner at teh office that he needed to have one tech, and that I didn't like cleaning up other people's messes (with the underlying message that he'd already chose his tech, and will end up paying the consequences because he has an office staff person that in incompetant & even worse, has sabotaged some computer stuff.)
Anyhow, relying on what one program says for ALL your security is not incredibly wise. Norton makes a pretty darn good antivirus program, but when it comes to firewalls, spy and malware, they tend to lack where they need to be workling and seem to be working when it's just competative software IMHO.
Be sure you got a clean copy of Foxfire direct from mozilla.org and be careful what websites and add-ons (plug-ins) you download.
For antivirus ware, I'd look to NOD. For anti-spy ware, there are plenty of places on cnet.com that have many, many reviews from those who know what's up.
If you don't know how to decompile a program, then don't assume the problem is from where a program says it is, as there are often rerouters, and in this case, it seems like it might be a plug-in to Foxfire, but where did you get that from???
Bottom line is not to download ANYTHING from the Internet unless you know what you are downloading and who you are getting it from!!! That also goes for visiting pages you don't know and opening email you don't know!
Because it is malware you appear to have and it appears to be attached to your browser, it is likely from another source. I'd send a copy of the file to someone in mozilla's boards who can decompile it and tell you where your info is going (if in fact it's going anywhere) or if its just Norton IS giving false info, which I've seen before - they don't like competition!