How do I prevent a fixed column from being displayed when scrolling ( possible bug )

Hi, I think I have found a possible bug on iPad using a trackpad ( see capture below ):
https://imgur.com/a/bWBmobx

When you scroll too much on the right or left, you can see twice the fixed columns which looks a little weird. Is there a way to hide it ?
Do fixed column use a different css class from the one hidden underneath ?

Thanks.