Why when my apps minimize why do they minimize into stacked rectangles instead of previewable files?

[Android Central Question]

It used to be I could scroll through my minimized apps now all of a sudden all my minimized apps are in a latter shap stack and I have to press them to pre view them which just opens the page anyway.

 

[Javier P]

Welcome to the forums. What device do you have and what version of android is it running?