When you drag a window to the side of the screen, your mouse must hit the edge before it will happen. You'll get a little indicator and outline when you get that simply release the the window. An Alternative is to use the WINDOWS + one of the four arrow keys.
WIN + UP Arrow, Maximizes
WIN + DOWN Arrow, Minimizes
WIN + LEFT|RIGHT, Cycles the Windows around in 50% splits.
If you do a vertical resize and your mouse hits either the top of bottom of the screen, it will give you the choice to take up the full height of the screen.
Logic without the fatal effects.
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