FireFox/Thunderbird: Won't save config nor save any extensions

[O. Hartmann]

Hello.
I have a long lasting problem with both Firefox and Thunderbird running 
on FreeBSD 6.X/AMD64. After I made a backup by just copying my homes 
directory onto a DVD+RW and 'reinstalled' it by copying it back to my 
new home folder, I run into trouble with bot mentioned utilities, 
Firefox and even Thunderbird as well. The problem occured is simple. I 
can add and delete addresses in Thunderbird, but I can not install 
extensions, they were never listed although they're on the harddrive 
(you know, that small box where I can select an add on and install it 
already downloaded to a place on harddrive).
Another thing is the position and size of the window. Yo know, when 
closing either program, after restarting it opens at the same size you 
closed it. That is not true in my case, the utilitie simply reopens at 
the size just at that time I did the backup.
In Thunderbird, I'm nt capable of creating some sort of signature as I 
can do this at my lab's computer, running nearly the same operating 
system's configuration and installation.

I tried to 'mtree' the working directory layout to reveal the 
differences and get rid of them, but it didn't work for me.

Is there something that can do the 'trick'? Please let me know, I'll 
appreciate any hint.

Regards,
Oliver