Some widgets, has there own GdkWindow, and when adding them to Xfce panel, they of course draw their own background, and it conflicts with the transparent panel if it was set so. I try to find the parent widget which hold the GdkWindow, and set my widget style to this holding window widget style, but it doesn't help. The widget background appears white. The widget I'm talking about is a GtkLayout, which I used it to implicate a moving /animated text(in a label). In GNOME panel, I think it is possible(because of the event when background get changed). I hope you find a way to fix this issue for widgets than own their window. Tal
Just avoid widgets that draw their own window, there is hardy any need for this.