=What steps will reproduce the problem? 1. Create a few pages with content 2. Move one of the pages quickly among the other tabs by pressing Ctrl+PageUp/PageDown

=What is the expected output? The tab should just move to another position among the other tabs

=What do you see instead? The content of the other pages (which changed positions with the moved tab) is deleted (usually totally, sometimes partially)

=What version of the product are you using? On what operating system? 2.03 on Firefox; Bug exists in 2.02 (Standalone Debian Package) too; OS: Ubuntu 12.04