Samsung Galaxy Note series support Multi-window feature. It is working better in Galaxy Note 5 comparing to its predecessors. But unfortunately after update to Nougat 7 from Marshmallow 6, there are some problems regarding with multi-window operations.
One is, while an app open in pop-up, it takes much time to reload or buffer. For example YouTube app switched to pop-up from full window, it takes much more time to reload. But there is no such problems in Note 3 which runs on Android 5.
Another one is, after opening two apps at a time, then close one app with back key, two apps are closing at that time. But there is no such problem in Galaxy Note 3.
These problems are common with two of my Galaxy Note 5 devices.
Hey @Fairysam, to help us troubleshoot, could you please submit a device error log when this happens again? From the Samsung Members application, tap the “Feedback” icon. Tap the Pen icon and then submit an “Error report”. Thanks!