The design option "Carousel Widget Horizontal Option with background" forces you to use a title that is underlined. You cannot remove the underline and no other titles have that. I want to use it but it causes this particular widget to be inconsistent with the other. A bigger issue is that when you turn the background off, it should be transparent, but it is not. All the other widgets can have their backgrounds turned off and the slide background appears, but in the carousel, even if you turn the background off, it appears white once published. It looks like the background is turned off on the stage, but you will see when you preview or publish the project, the white background remains. Here is a video showing the issue.

In doing some more testing with this and I determined the background of the widget IS turning off, however there exists some other white background only on the carousel (in every version of the carousel) that you cannot control. For example, my slide background is blue, and when I make the carousel background solid red at 50% opacity, the widget background appears purple in program because the blue and red mix. But when I publish or preview, the background looks bright pink because the 50% red mixes with the white. The white is always there when you publish, you just can’t see it in the program. Definitely a bug.