Using cover block without setting color or image

Hi,
I am using the cover-block to set a color background over another element. But I don’t want to set any color nor image to it in the block settings (explanation why further below). But then there is always this block-cover window with the color palette in front of the cover content and I am not able to edit the content without applying a color to the cover. How can I remove the window? Or is there a better block to use to add a color background that I can apply in the same way?

I chose to do it this way because if I use the cover block and set a color in the block settings and add opacity later through the customizer, it applies the opacity to all elements (paragraphs, for example) contained in the cover block.

So I choose to not apply any color in the block settings and add background-color with the dim effect through rgba values in the customiser.

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