Voice Blog theme: How to remove”next” & “previous” blog post sliders

Running Voice Blog theme. I have recently run an update, and some sliders have appeared that I haven’t seen before and can’t find a way to get rid of (I think they are called sliders – don’t know all of the technical terms, I’m sorry). When you open a blog post, a panel slides in from the side showing the previous (or the next) blog post. It blocks the blog post that is open for reading, and I can’t seem to get rid of it. The “X” on the slider is unresponsive, so I can’t just get rid of it that way. I have been through my plug-ins, widgets, what-have-you, but can’t find anywhere to turn these things off. Is anyone able to help please? Much appreciated.