SOLVED: Look like it's Adobe's fault: http://www.stinkbot.com/blog/archives/69 Just turn off "Stop on Debugger()" in the run menu in XCode I am a newbie to programming on the Mac, but not programming in general. I created a simple application to load a web page in a WebView. When I load apple.com and browse around, it works fine. When I browse to Facebook it crashes with signal 2 (SIGINT). Any idea why this is? Should I be using a different control for web view? This happens on both debug and release builds.