It is amazing how bugs go through versions and years. Visual Studio’s IDE dockable windows framework is cool, no doubt. But it was since 2005, if not earlier, that tool window undocked by a double click while application is running (debugging session active) is brought to wrong position and is tending to go out of screen area being re-shown.
This is exactly the behavior in 2008 version, regardless of reworked framework and fancy icons/hints/placeholders for the window being dragged. But just now it was even better. I double clicked “Find Results 1” window to maximize the window… and it disappeared. After looking for it through menu and other GUI elements, I finally found it at the rightmost border of the secondary monitor:
