BetterYTM-Mirror/assets/style/aboveQueueBtns.css

#side-panel ytmusic-tab-renderer ytmusic-queue-header-renderer {
  position: sticky;
  align-items: center;
  top: 0;
  z-index: 2;
  padding: 16px 8px;
  margin: unset;
  background-color: #030303;
  border-bottom: 1px solid var(--ytmusic-divider);
}

#side-panel ytmusic-tab-renderer ytmusic-queue-header-renderer.hidden {
  z-index: 0;
}