Prevent category's thumbnails to change when you modify the category's image

[Aurelink_]

Hi guys ! 

 

On prestashop 1.7 I'm calling on my menu the category's images and the category's thumbnails and they are 2 differents images.

I set first my category's image then the thumbnails.

But every time I change the main image, prestashop regenerate the thumbnails too and it's looks like the main one 😕 

So I would like to know if it's possible to prevent the category's thumbnails image regeneration when I change the main category's image.

I put 2 images on exemple, the first one is the default state and the second picture is when i change the main category's image

Thanks guys

Edited December 18, 2018 by Aurelink_
oversight (see edit history)