I have been using the same basic installation for something like five years.
Ubuntu 9.04 upgraded to 10.04 and finally 12.04
Recently I decided to upgrade my HD to a 2TB hybrid and figured now was the time to install fresh and use the 64 bit version of Ubuntu 12.04
I first performed a test install on a smaller drive...all worked well,
so I went ahead and put the 2TB drive in place, installed the OS and Gnome.
I then applied all updates and gave everything a good test.
System performs real well...but there is one odd problem that I just plain do not get.
This /only/ happens with Firefox and as far as I've seen /only/ if I am posting to Craigslist.
If I enter text into the "subject" field, the browser behaves normally,
Investigating further I found this anomalous behavior does /not/ occur if I use Xfce.
I also tried Unity and that gave the same results as Gnome.