What seems to happen in this configuration with a low height screen: The element is positioned with _showPopoverAndOverlay https://github.com/sorich87/bootstrap-tour/blob/master/build/js/bootstrap-tour.js#L531 It's positioned in a way that goes out of the window. Then it tries to focus/scroll to the element. It calculates the position where it needs to go, and somehow this triggers another showPopoverAndOverla call.
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