On a past contract they asked me to create a prototype for a window snap preview.
This is a streamlined version of the original prototype with branding removed.
Click the mock browser window's title bar and slowly drag to see a snap preview window as well as an outline of the snapped window placement.
For best results, run the app maximized. On the initial run, one of the window's title bar may be off-screen. To fix, just close the maximized app and open it again.