Hi guys,
I just learnt that it is called HTML Accesskeys.
I found this site
http://juicystudio.com/article/firefox2-accesskeys.php that talks about it and look at this comment
http://juicystudio.com/article/firef...s.php#comment6.
It is actually a workaround for going back to FF1.5 style.
I'm using it now as I type this message.
If you are reading this it's because it worked because I used ALT+S to send the post

.
EDIT
Which means that you can use:
alt+b=bold on/off (without hack it's alt+shift+b)
alt+i=italic on/off (without hack it's alt+shift+i)
alt+u=underline on/off (without hack it's alt+shift+u)
alt+q=quote on/off (without hack it's alt+shift+q)
alt+c=code on/off (without hack it's alt+shift+c)
alt+l=list on/off (without hack it's alt+shift+l)
alt+o=list2 on/off (without hack it's alt+shift+o)
alt+p=picture on/off (without hack it's alt+shift+p)
alt+w=web url on/off (without hack it's alt+shift+w)
and...last but not least...
alt+s=submit/send post (without hack it's alt+shift+s)
It works again

! Honestly, I was almost going crazy here
Cheers