PR #662 introduced the auto-generation of page descriptions when none is provided in the page front matter. On many projects that I support, this behavior creates nonsensical descriptions, for example, the following is entirely blank:

Search engines can do a better job at auto generating a page's description.

This issue proposes that the page auto-description feature be opt-in for projects that want it, rather than the default.

/cc @LisaFC @emckean @geriom