System Information
Operating system: Windows 10
Graphics card: nVidia 1050ti

Blender Version
Broken: 2.83lts

Short description of error
view2d.scroller_activate seems to not have any effect on inner list boxes.
I expected it to scroll up or down while shorcut key is held down and the mouse is 'dragged'
For example, try scrolling through a long list of shape keys. the view2d.scroller_activate affects the whole properties panel scroll ability, but not the inner, actual list.

also related, when i use Pan in the shape keys list, it pans the whole properties panel. I just want it to scroll the actual list i am over, such as a long shape keys list.

Hoping for confirmation of issue, or for someone to tell me i simply do not know what i am doing, which is likely the case.

Exact steps for others to reproduce the error
Try to scroll through a long list of shape keys using the shortcut key (not left click) for view2d.scroller_activate

Request: if this is not a bug, please tell me what combination of clicks, drags and ro key presses i need to do to scroll within a shape keys, or other, long list by Click and Drag on the list it self, not on the scroll bar. Very similar to Pan style, but just in the list i am hovering on/is active at the time.

Thank you