color switch on product grid

Hello
I activated “Show attribute label on products” on my color attribute. all attributes have “Enable swatch” on, so at product level, I have the color swatch working.

but at product grid level, the color options are not displayed. instead the label are shown over the picture.

If I disable “Show attribute label on products”, obviusly, labels are not shown anymore, and still not the color swatch. Did I miss something ? is any additionnal plugin required ?.