Rated 4 out of 5 stars
[18:54:47.972] "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:13.0) Gecko/20100101 Firefox/13.0"
changeset - 92132:f16e48c88ac3
0. Open any site, about:newtab is just OK
1. Type anything in url bar
2. ALT + ENTER
Firefox is trying to understand/open what you typed in the CURRENT TAB however she should did this in a NEW TAB
This should be fixed by disabling Omnibar, so it's Omnibar's fault
Posted a new update that should address this. Thanks for the report.