weird firefox behavior, any ideas?

[Tom Horsley]

Here's the strange case:

When I have an active NX connection from my home system
(running the nomachine nxclient) to my work system
(running the freenx server from the fedora repos),
firefox (on home system) slows to a crawl.

Things like expanding or collapsing a sidebar bookmark
item sit there for several seconds after I click on
an item.

I thought this might be something like dynamic libraries
needing relocation to conflicting addresses, but if I
start firefox first to get the libraries loaded, the
existing instance of firefox slows down after I start NX.

I'm not doing anything weird to my network (that I know
of - maybe NX is doing something behind my back), and
I'm operating through a ssh forwarded connection, not
starting a VPN or anything like that. A network monitor
shows the normal traffic due to NX at around 3K bps,
so I'm clearly not bogging down the network, and I
have 8 gig of memory on this system, almost all of which
is free, so I'm not running out of memory either.

Nothing else on the system goes funny in the head, it
seems to be just firefox.

Any ideas out there?