Suggestion: Allow user to set a delay for expansion of a rolled up fence.
Reason for this suggestion: Suppose that you have several rolled up fences stacked vertically. If you want to access anything below the top fence, it is impossible to do so by moving the mouse downward from above to the 2nd, 3rd, etc. fence. This is because the moment the pointer is placed over the first fence, it expands, obscuring the view of the fences below it. Instead, the user is forced to do a weird little dance, shuffling the pointer toward the left or right side, then moving down, then moving back over to the desired fence.
If we could set a short delay, say maybe 1/4 of a second, before the fence unrolls, this would allow for a more natural movement of the mouse as the user can slide the mouse down past the 1st, 2nd, etc. fence(s) without having it instantly obscure the fences below.