Screen shifts when popup is shown

Whenever a popup window is shown the main screen behind it shifts to the right by a few pixels. When the pop is closed the screen shifts back again. It’s working fine just kind of weird and annoying. Can this be fixed?

It’s the scrollbar showing and hiding with the popup. You can try to override it with custom css but not sure if it would work flawlessly, it could cause popup to behave unexpectedly in some cases.