I can confirm that it's completely broken on PrimeNG 17.8.9 and has made virtual scrolling tables, completely unusable. Once, I scroll past the first "page", all entries after it are stuck in a loading state, and the scroll bar jumps around. Changing the virtualScrollItemSize doesn't seem to make a difference, and is only resolved when setting the scrollHeight to a fixed number of pixels

https://stackblitz.com/edit/oetsny-rdsoxe?file=src%2Fapp%2Fdemo%2Ftable-virtual-scroll-lazy-demo.ts

On PrimeNg 17.8.8, it was also broken, with the bugs stated below.

(#16185) If I set the virtualScrollItemSize to be less than 50, when I to scrolled to the very bottom of the virtual scrolling, lazy loaded table, I was unable to see the very last few rows in the table, and scrollbar would jump up when trying to scroll to them

(#13370) If the table has the rows attribute set, when I scroll from the top to the bottom of the table (so I effectively skipped some "pages" in the middle), then scroll up to the middle of table, the table would be stuck in a loading state - this has been been a bug for over a year, since at least PrimeNG 15.4.1

I believe the virtual scrolling implementation needs to be be re-evaluated as it has a lot of different bugs

It is not related to changes in virtualScrollItemSize . In the example, i am using the default sizes.

@sotjdisc, I understand, this bug happens when setting the scrollHeight to 'flex'. I was adjusting the virtualScrollItemSize, to see if there was any relation to the existing bug #16185

bump, we're experiencing the same issue

Yep most tables using scrollHeight="flex" + virtualScroll="true" are broken. Also the table header disappears halfway when scrolling to 50% of the table.

i want to blame this commit - e7b611b

i believe this PR will fix it - please merge - as all flexheight tables/trees are broken atm.