Ion virtual scroll rendering problwm


I have been using virtual scroll to load my set of data, whenever from the list page if i navigate to some other page ,I could see only some of the items are getting rendered in list ,after a flicker in a second remaining items are rendered?Could any one help me with this issue.In ionic 4 i have used buffer ratio, the problem seems to be fixed in version 5 i could not able to see the buffer ratio option itself