diff --git a/docs/TODO b/docs/TODO
index 323bbb771c..8c69e3fbdb 100644
--- a/docs/TODO
+++ b/docs/TODO
@@ -17,6 +17,7 @@
  All bugs documented in the KNOWN_BUGS document are subject for fixing!
 
  1. libcurl
+ 1.1 TFO support on Windows
  1.2 More data sharing
  1.3 struct lifreq
  1.4 signal-based resolver timeouts
@@ -192,6 +193,13 @@
 
 1. libcurl
 
+1.1 TFO support on Windows
+
+ TCP Fast Open is supported on several platforms but not on Windows. Work on
+ this was once started but never finished.
+
+ See https://github.com/curl/curl/pull/3378
+
 1.2 More data sharing
 
  curl_share_* functions already exist and work, and they can be extended to