Coraline by Automattic theme
An object - it may be a widget - has appeared on each page on my site. It is superimposed over the featured image near the top on each page. It looks like a widget designed to scroll side-to-side. It seems to have appeared "out of nowhere." I am not aware of any action I've taken that can account for it's presence. I do not see any editing function that will remove it.
I do not know the specific technical language to use to identify this issue more precisely than I have. Your input is requested.