/* Sticky only the margin sidebar that contains your support box */
@media (min-width: 992px) {
  aside.margin.sidebar:has(.supporting-maverick-sidebar) {
    position: sticky;
    top: 15rem;          /* tweak: 4rem–6rem depending on header height */
    align-self: start;  /* helps when inside CSS grid */
  }
}

/* If sticky still fails, it’s almost always an overflow ancestor */
@media (min-width: 992px) {
  aside.margin.sidebar:has(.supporting-maverick-sidebar),
  aside.margin.sidebar:has(.supporting-maverick-sidebar) * {
    overflow: visible !important;
  }
}