When you hover over a running application and it shows a preview that you can click on, if you move up to click it disappears if you are too quick. Compare this with the built in windows task bar which doesn't fade, it doesn't disppear. You can best see this in the gif I attached.

Is there a setting to turn off the fade, and if not, can this be fixed or have a setting to turn the fade in off?

The give moves pretty quick. The first time I move the mouse up, it disappears. The second time, when you see the background is when I was slightly slower and the preview didn't disappear.

I think the thumbnail preview is what I was looking for. I've attached the debug info anyway (prior to changing the setting).