Is there a way to open a particular app always on pop up window ?

[Knightfury]

Let's say I want to open Instagram from app drawer it expands and it looks really weird. Only way I found was to use the edge panels. However this annoying because if we click on the notification drawer it will open in full size. Is there a way where we can set a particular app to open up in pop window only ?

[rush20]

You can by keeping it open in background
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