I am having the same issue. I identified Eset as the culprit by downloading a free app called Window Focus Logger from hxxp://www.adminscope.com/downloads/window-focus-logger/ and the very next time that my Chrome browser lost focus (while I was typing into a forum on Spiceworks) I saw that the process name was "egui".
I have attached a screenshot highlighting the last 2 times that "egui" took focus away from the window I was using.
I am using Eset NOD32 Antivirus version 12.1.34.0 .