2

Just allow to select scroll mode for applications/kwin by clicking first, second buttons and scroll.

For example, while using this behavior over non-client area, user may switch between:
- Change transparency
- Change sound volume/level
- Switch between all window app's
- Switch between all window on current desktop
- Minimize/Unminimize window to border/caption/title
- Switch between desktop
- Minimize window
- Disable/Enable WM shortcuts, like ALT+LBUTTON, SUPER button, etc.

Gwenview scroll mode (when clicking inside Gwenview window's client area):
- Next/Previous image
- Next/Previous directory in history
- Zoom/Unzoom image
- Rotate image

On some widgets (for example scrollarea):
- Flip scroll axis to 90 degrees
- Flip scroll axis to 0 degrees

Additionally, add keyboard shortcuts for scroll mode.

So I can move mouse cursor above non-client area of GIMP window, click left+right+scroll (I now have changing transparency mode), I click again left+right+scroll (I have changing global sound level mode), I again click right+left+scroll (I now have switching between app's windows) and I scroll, so I have toolbox at top.

Idea is invented, cause Linux doesn't support touchscreen good, so we could give users alternative.