diff --git a/_layouts/default.html b/_layouts/default.html
index c155fa6..a6e108f 100644
--- a/_layouts/default.html
+++ b/_layouts/default.html
@@ -59,7 +59,7 @@ layout: table_wrappers
{% endif %}
{% endunless %}
- {% if site.heading_anchors != nil %}
+ {% if site.heading_anchors != false %}
{% include vendor/anchor_headings.html html=content beforeHeading = "true" anchorBody="
" anchorClass="anchor-heading" %}
{% else %}
{{ content }}