Filters, rows and children rows

Let’s say I have a dhtmlxgrid containing five rows. Each row has some children rows (loaded dynamically), and some of the grid columns are filtered (using #select_filter). When I expand only 4 rows of the grid, my filters work well. But when I expand all the rows, I can’t no longer use my filters. They literrally disappear. Can someone tell me why and how to fix that?

P.S: I didn’t use custom filters. I used those provided by default by the lib.

Unfortunately the issue cannot be reconstructed locally.
The following sample works well for us:
dhtmlx.com/docs/products/dht … ering.html

If issue still occurs for you - please, provide with a complete demo, where it can be reproduced.