Swicth button shows sometimes a missing pixel column

[issam.chorfa]

I'm working on switch button example where i have 2 rectangle one is the background and another one is the swicth indicator.
Rectangle {
id: background
.......
color: "#777777"
}

    Rectangle {
        id: indicator
       ........
        color: "#ffffff"
    }

The problem is sometimes when i move the indicator the background rectangle show a missing pixel column.

Any idea how can i solve it ?

[NYBL]

maybe post a reproducible example?