Disclaimer: I'm only moderate linux user, KDE fans, and a tester so I might be wrong but still I made this in hope it can spawn more ideas or correction

The first idea was posted before I'm joined this forum here https://bugs.kde.org/show_bug.cgi?id=373027
The second idea described below:

I have Gwenview Version 16.08.3 on my parabola GNU/Linux Libre (Archlinux -based) , When zooming image in gwenview more than window fit, a thumbnail zoom pan (or whatever name it is) will pop-up above right zoom slider like this:



My suggestion is to implement more convinience thumbnail zoom like Okular document reader did



I assume that the philosophy of user main focus is in the main image and not in the image gallery slider
Benefit:
1.Doesn't stand in user way (The thumbnail is in image gallery slider not in the image itself)
2.Doesn't reduce viewing area (The thumbnail zoom not in the thumbnailed image)
3.Precision (Always know your viewing area, no wait for thumbnail to auto dissapear or reappear)
4.More visible contrast (Not much deal with high transparency)
5.Cool ?

Thanks for your attention