Comment 1 for bug 850863

This morning I experienced a similar problem with Firefox. I had both firefox 6.0.2 and thunderbird 6.0.2 open (but and when I tried to delete a bookmark in firefox by right clicking and selecting delete, the entire submenu box disappeared each time I tried to move the cursor into it. Closing out firefox and restarting it resulted in normal operation.

I should note, that in both computers where this behaviour has occured, the computers are in different homes and the other computer is running the latest version 3xx (or so) thunderbird and firefox programs from the ubuntu repos. Both computers have the latest ubuntu updates as well.