HTML toolbar menus can be resized even if they are hidden

Currently, when a toolbar panel is hidden ( not closed ) the mouse pointer is
still changing to a “resize” arrow if the mouse passes exactly over the
BORDERS of the hidden window. This prevents mouse clicks to reach the VC
buttons. Is there a way to prevent this from JS ?

Would setting pointer-events: none; on the top element work?

Tried it just now, I’m setting the property through JS this way:

this.ingameUi.style.pointerEvents = "none";

And I can see with the GT Debugger html inspector, the CSS property pointer-
events: none appears over the element ( it didn’t before ). However, it
doesn’t seem to have any effect, since I can still see the arrows when
hovering where the window border would have been, if the window wasn’t hidden.

Radical but… display:none; ?