Slider widget sometimes with blank space below

Hello,

I installed the Colormag theme, and inserted the Slider widget in that area. It is showing allright but, sometimes, when you go and open the site as a visitor, some blank space apears below the slider widget, while rendering (loading).

This is also visible in mobile version.

Looking the code, I found to many </div> at the end of that area. I dont know if it is related.

Please, can you look at it?

Thanks

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