Show reader as one button in taskbar

[Jack2361625457eb]

I have seen a couple discussions on this topic and every time people said that it isn't possible. However on my laptop I had only one button in my taskbar while multiple documents were open. It felt amazing, didn't have to worry about finding the last document I was on when I had multiple open. However, after I restarted my laptop it reverted back to what it has always been. But now I know that there is a way to only need one click in the taskbar. Does anyone know how to activate that setting now?

[Jack2361625457eb]

If it helps, the taskbar icon looked like the acrobat reader symbol in a white rectangle(like a piece of paper) instead of the regular acrobat symbol in the red square.