Back button on note 4 used to open slide bar on one side of the screen (which could be customised) to open the app or our liking. Whenever I used that function it never intervened by refreshing, stopping, restarting browser, youtube video, etc. But unfortunately, this Samsung Galaxy Note 8 £1K plus mobile phone doesn't take care of that.
Firstly, you have to interject ongoing video to use this function as opposed to note 4.
Secondly, if you want to increase or reduce the screen size by dragging it into small box or multi window option, whatever app you are using it "refreshes" itself or get paused by the function. If you are streaming on browser it can be worst nightmare to restream the whole thing again. Never used to happen that in Note4.
Lastly, we liked that side bar (used to appear by pressing and holding back key) in Note 4 to add small window of other app whilst doing whatever was going on without even pausing the video or video not even get paused by this function unlike Note 8. Strange. In Note 8 back key doesn't have this function. You have to press close all key (left key) to use this function. Which is bad itself. One can mistakenly close the apps without wanting them to be closed. So, everything gets paused. So ambiguous. I don't know who did that and why.
So, I think they should go back and study Note4 and send update on this function to add more accessibility infact usability without interfering other running apps as it used to be in Note4.