Panel-Header with higher Captionbar via Theme.mixin

Hello everyone,

I have the following problem and have attached a small sample project to illustrate the case. I placed a panel with ShowHeader, AutoSize set to true, AutoSizeMode set to GrowAndShrink, and several text boxes in it. Everything works fine with a default theme, but when I include a .mixin theme, the panel doesn’t work as expected when I use more space for the panel header by changing CaptionBar->Horizontal->Height.

Do you have any ideas, thanks in advance