diff --git a/docs/cmdline-opts/ssl-sessions.md b/docs/cmdline-opts/ssl-sessions.md
index 054492b41f..bb1e251e73 100644
--- a/docs/cmdline-opts/ssl-sessions.md
+++ b/docs/cmdline-opts/ssl-sessions.md
@@ -33,3 +33,6 @@ The SSL session tickets are stored as base64 encoded text, each ticket on
 its own line. The hostnames are cryptographically salted and hashed. While
 this prevents someone from easily seeing the hosts you contacted, they could
 still check if a specific hostname matches one of the values.
+
+This feature requires that the underlying libcurl was built with the
+experimental SSL session import/export feature (SSLS-EXPORT) enabled.