Do you see blank screen or permanent welcome message?
I saw default ones (amazon and so on) but my groups are still there with no markers. However after reboting firefox and opening my previous sesion my bookmarks are alive again (but I lost the titles, despite of being there if I click right botton and go to the cofiguration of every mark)
You need to set background image which is not white or change the color of titles in the settings.
Customer support service by UserEcho