+This behavior can be altered by customizing
+@code{buffers-tab-filter-functions}. Setting this variable to
+@code{nil} forces display of all buffers, up to
+@code{buffers-tab-max-size} (also customizable). More complex behavior
+may be available in 3rd party libraries. These, and some more
+rarely customized options, are in the @code{buffers-tab} Customize group.
+