diff --git a/docs/proposed/config-split.md b/docs/proposed/config-split.md
index fe750f4..fd8a8c7 100644
--- a/docs/proposed/config-split.md
+++ b/docs/proposed/config-split.md
@@ -100,7 +100,7 @@
 of the "Mbed TLS modules", "Mbed TLS feature support" and
 "Module configuration options" sections into the
 ["TLS feature selection"](#section-tls-feature-selection) and
-["X.509 feature selection"](#section-x.509-feature-selection) sections. That
+["X.509 feature selection"](#section-x-509-feature-selection) sections. That
 way all TLS/x509 options are grouped into one section and there is no
 section dedicated to non boolean configuration options anymore.