Window manager problems

[Tethys]

I had an old machine running some ancient version of Fedora (13 or
something, I think). All was good. But obviously obsolete and probably
insecure. So I upgraded to Fedora 20 before Christmas. I typically use
fvwm. However, when I move windows, an image of the window in its
previous position remains. See the following screenshot:

http://pics.astradyne.co.uk/ref/150101--fvwm.png

Note that there is only one terminal open here. The rest are ghost
images. It doesn't do this if I use GNOME or KDE. I initially thought
that it might be an fvwm problem. But I can replicate it using icewm
as well. There are two ways to start the window manager - via the
session type dropdown box, or via a user script (~/.Xclients). Playing
around with a few options, I get the following results:

Starting from session dropdown:

fvwm - broken
icewm - working
KDE - working
GNOME - working
XFCE - working

Starting from ~/.Xclients:

fvwm - broken
icewm - broken
xfwm4 - broken
mutter - working
kwin - working

This is with Intel graphics:

macbeth:~# lspci | fgrep VGA
00:02.0 VGA compatible controller: Intel Corporation 4 Series Chipset
Integrated Graphics Controller (rev 03)

I tried compiling a new version of fvwm from source, but that showed
the same problem. icewm and xfwm4 are intriguing in that they're
broken from ~/.Xclients but working from the session dropdown. Any
ideas?

Tet

-- 
"Java is a DSL for taking large XML files and converting them to stack
traces" -- Bulat Shakirzyanov