Hi,
This happens for me a couple of times per day in the request module. After I've hovered over a request the preview boxes gets stuck like the screenshot below shows.
Last time it happened right after switching from the admin module to the request module. It also occurs when clicking the "Add/remove columns" if I've hovered over a request just before.
Windows 10, IE11, SDP 9317, MSSQL. (It also happens in MS Edge)