Shopify 2.0 adding _50x to the end of image file name uploaded in content admin page

[GoodfyLabs]

So 

I use IMPULSE Theme 3.4.0

They have the swatch resource when you add a Color Option named like  Shine Yellow 

you should upload a file named shine-yellow.png and then the swatch will present that file as Color

But I have noticed that Shopify is rendering  looking form a shine-yellow_50x.png and getting a 404

How to stop this behaivior ?

( take a look ) 

[Mako88]

Did you find a solution to this?