Deleting unselected emails

Why does emclient delete emails next to the one I’m deleting as well? It doesn’t happen every time, but still too often. This never happened with my older versions. We’re using 10.0.

That can happen when the eg: del key is playing up when you press once but it deletes twice. It can also happen with glitchy mouse buttons.

I usually delete using the delete icon at the top of the page. No problems with sticky keys for any other software.