Hi all, I've noticed a new concern following the recent install of 10.9.2. The "lockup" has occurred several times on my Macbook Air (13in, mid-2013). By lockup/freeze, I mean complete loss of access to anything on my screen with everything on the screen, including the icon, freezing in it's location and no response to any key or touchpad input. The screen and computer basically stop responding to anything. This has happened for me when browsing with the latest version of Firefox. The only way to remedy the situation is a hard-restart with the power key. I suppose I associate it with 10.9.2 as it's the most recent software update and I've not changed anything else in my system configuration or my software for awhile. Anyone notice something similar? Thanks for your thoughts!