There were 3 addons not supported as yet. I only used those rarely anyway.
The test video offered after install was very jerky. Both image and sound.
Then there is this video:
EDIT: I just spent 30 minutes trying to find out the below. Thought this might help others.
Hide the tab bar when there’s only one tab open
To restore Firefox 3.0’s default behavior of hiding the tab bar when there’s only one tab, in Options/Tab, uncheck Always show the tab bar.
Edited by buddy215, 01 July 2009 - 03:59 PM.