User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:2.0b12pre) Gecko/20110220 Firefox/4.0b12pre Build Identifier: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:2.0b12pre) Gecko/20110220 Firefox/4.0b12pre Since the nightly build of 2/18 minefield 64bit in Windows 7 looks all broken up. As you can see in the picture, the tabs, the icons, the menu button, even the G in google are broken up. The menus have dotted lines down the middle. 2/17 works just fine. This is a brand new profile, nothing installed. Reproducible: Always Steps to Reproduce: 1. update to 2/18, 2/19 or 2/20 nightly 2. open old profile 3. open new profile Actual Results: The menus/icons and tabs are broken up and have funny lines. Everything should look normal as it does if I installed the nightly for 2/17