Hi,
I found problem with editing last row of table with virtualX: true. Here is example
http://jsfiddle.net/9s8g4e5q/1/.
If I double click on any cell in
last row to edit, first row disappears. If I click again, second row dissapears.
Problem is probably in method
_scrollRowVirtual. In version 3.3.0 on line 5068, there is condition ...
if (td_bottom > htCont - htSB - marginTop)
... where htSB is height of horizontal scrollbar. But scrollbar is not part of container pq-grid-cont, so htSb should not be probably in that condition in my opinion.
I hope my report will help to correct this.