Here is a sample site:http://issues-71f980.webflow.io/ that experiences the same issue.
Here is the read only link: https://preview.webflow.com/preview/issues-71f980?preview=f27e262c8d3df7d73d8a49730150951c
Here is a screenshot of the behaviour: http://screencast.com/t/zuBH8EXdoHS