virtualScroll loads new the items only at the bottom


I have an issue with the virtualScroll, it loads the new items when I reach the last loaded item at the bottom ( or at the top if I scroll up )
From what I understood, it should load before, so we don’t see that we are loading the new items.

The code I use:
<ion-list [virtualScroll]=“messages” [bufferRatio]=“3” approxItemHeight="10px"
approxHeaderHeight=“0px” approxFooterHeight=“0px” >
<ion-item *virtualItem=“let message”>
<component [message]=“message”>

The items are bigger than 10px, but I think it should be easier to load if I indicate a smaller height.

Thank you for your help.