TRIchEdit clear background in standard windows but not in styled version

[Cedomir Plavljanic 0]

I have a strange problem with TRichEdit.
I create a transparent successor to the TRichEdit class with an image as background.
If styled is active all work. But if is standard windows active do not work properly.

In message WM_ERASEBKGND I first erase background and then paint image but when windows draw content of richedit class it first call FillRect and clear background. This das not happen with styled version. 
What Delphi change in settings for trichedit in styled version when this approach work? I can not find reason for that.

Both version call procedure CallWindowProc from user32  and in this procedure clear again background in standard version but not in style version. 

See pictures