How to deal with category thumbnail, menu and cover images?

[lifaown01]

I don't know what is wrong.

Please see the attachment, I just want to change the category icon but it looks like there is a bug or they are somehow dependant.

I tried to upload just the icon and there was no changs showing even after multiple hard refresh. Then suddenly it apeared after uploading the icon in all 3 places and refreshing a few times. THen I deleted the cover photo and the thumbnail disapeared? Can someone please explain to me how to use it and what to use for which section?

(I hope that the cover photo doesn't have to be the same as thumbnail as this would be pointless as these are two completely different purpose sections so they can't use same image.

Logically the icon has to visualise the product and the cover I guess has to be empty as it has text on it. It would be much simplier if instead of cover image being background to the description category text there was a normal icon image NEXT TO the text.)