ScrollingBar still being 'there' even when everything should make it not there?

As you can see, my frame is being ‘clipped’ by the scrolling frame, where the bar would be. Even though, the bar has a thickness of 0, transparency of 1, and no bar images. All 3 of those things I’d imagine should make the bar non existent (visibly), however I still get cut off UI elements


Upon further testing, it seems to be due to BorderSizePixel. However, I still believe this to be a bug, as I have it set to Outline and thus should not be causing any inset

With no border

With border

As you can see, the border seems to make the scrolling bar visible again (I did not change any other properties between screenshots, other than BorderSizePixel)

Larger the border becomes, larger the scrolling bar becomes

Repro
Scrolling bug.rbxl (24.6 KB)

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