Tesco online shopping problem with firefox 3

[dc]

Binary package hint: firefox-3.0

Tesco online grocery shop does not respond very well (intermitent but often) using Hardy Heron complete with firefox 3. Some windows fill up with garbled text and a message keeps popping up to ask if I want to download a page (which shouldn't happen). Dual booting with windows xp on laptop, also dual booting with windows me on desktop, same problem on both but xp dual boot laptop is worse. All is ok when I use windows.

ProblemType: Bug
Architecture: i386
Date: Tue Jul 22 20:19:08 2008
DistroRelease: Ubuntu 8.04
NonfreeKernelModules: nvidia
Package: firefox-3.0 3.0+nobinonly-0ubuntu0.8.04.1
PackageArchitecture: i386
ProcEnviron:
 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: firefox-3.0
Uname: Linux 2.6.24-19-generic i686

[dc (willowclegg-nethybridge)]

could it be that I need to download extra programs or applications to get tesco internet shopping site to work in firefox 3 on ubuntu hardy heron?