SubWindows bug when change Css

I use MultipleForm demo program with VS code.
If we switch property of subWin form ElementFont to efProperty to efCss all browser content will move when move subForm and componeents of subform are drawn at the top of parent form.
Even if we go back initial efProperty we don't return to the starting state with normal behavior.


We could reproduce this and we're investigating to have this fixed.