It is the same as reported in this case https://servoy-cloud.atlassian.net/browse/SVY-19171 but Servoy NG Grid is not using getLastDisplayedRow()/getFirstDisplayedRow() in TiNG, and that is a log from a TiNG client, right?
Can you create a (private) case for this, and add a link to (a sample of) your deployed app so we can debug it?