How To Disable GNOME’s Overlay Scrollbars (Have The Scrollbars Permanently Visible)

This article explains how to disable GNOME’s overlay scrollbars, so that the scrollbars are always visible. GNOME/GTK applications use overlay scrollbars by default in order to maximize screen real estate. For most applications (there are some exceptions, like GNOME Terminal which has the scrollbar permanently visible), the scrollbars are hidden by default, being partially shown when the pointer is moved, and being completely visible only when placing the mouse near the scrollbar.