This is a weird bug. According to reports, typing: ‘File://’ (no quotes) into almost any app with almost any character after that will crash it. Also interesting is that MacRumors points out that pausing between the ‘//’ and the last character will not crash the application.
What’s worse is that filing a crash report causes Crash Reporter and Console apps to crash. Here’s how to fix it, according to MacRumors. You will have to type the following into your Terminal (Applications>Utilities>Terminal):
sudo sed -i -e 's@File:///@F i l e : / / /@g' /var/log/system.log
Website TheNextWeb took a much deeper look at the bug here.