Why my GRID header has no color

Using the lastest version of the GRID. When the grid show up, I can not see any color on the header portion.

With the setting of



I should see the colored the grid header with vertical bar separate them such as


But I can only see the plain AAA BBB CCC and DDD with no color and vertical bars in the header.

How can enable them?

Unfortunately the issue cannot be reconstructed locally.
The following sample works well:
dhtmlx.com/docs/products/dht … _grid.html
If issue still occurs - please, provide a complete demo where the issue can be reproduced.