The Window Buttons area (wba) is in the middle of my (vertical) panel. So there's items above and below the wba. With a lot of open windows, buttons disappear "underneath" the items that are below the wba. I'd expect the buttons to become smaller but not move beyond the end of the wba. Screenshots will illustrate what I have problems with putting into words I guess.
Created attachment 3536 Screenshot 2 showing the problem
Confirmed, I am using the panel horizontally and the same thing happens. If any buttons do not fit on the panel, they simply aren't shown.
I would propose adding scroll buttons (left/right/up/down arrows) when the (number of items)*(width or height) is greater than the allocated area.
This is already fixed. An overflow button is shown that displays the remaining windows in a menu.