error building site: render: failed to render pages: render of "home" failed: "/home/runner/work/bookdown.org/bookdown.org/themes/hugo-xmin/layouts/_default/list.html:27:90": execute of template failed: template: _default/list.html:27:90: executing "_default/list.html" at <$.Site.IsServer>: can't evaluate field IsServer in type page.Site