Black border on prototype view

Hey ya’ll, quick question about previewing prototype links in chrome. We always setup our desktop-viewport artboards at 1440px wide, and thus have our chrome preview windows resized to that exact size – This has been bugging me for a while now, but why is there a black border on the right side of the viewport? Here is a screenshot of what I mean, this happens on every project:

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For the record, when I preview the exact same artboard, with the exact viewport dimensions on Figma Mirror the black border is gone.