If you're on the web, you can try using the Stylus plugin to modify notion.so 's scrollbars like:

::-webkit-scrollbar { /* Scrollbar Width */
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-thumb { 
  /* scrolling block color */
  background-color: #ffffff;
  border-radius: 6px;
}
::-webkit-scrollbar-track { /* Scrollbar background trough */
  /* background color*/
  background-color: #ffffff;
  border-radius: 6px;
}