TAdvPageControl TabBackgroundColor

Under Win10, Delphi 12, TMS VCL UI Pack ( latest ) the TabBackgroundColor of the TAdvPageControl is not appearing with the color as chosen in the Inspector. It appears to be only when a Style has been applied to the project. The same app under Delphi 11.3 with same ( ) VCL UI it works as required, with the chosen color appearing in the application. Is there a way to get it to honour the color choices as in Delphi 11 ?

I retested this here in a Delphi VCL app but I could not see an issue with using TabBackgroundColor for TAdvPageControl. If a problem persists, please provide more details how to reproduce this.