diff --git a/UserDoc.md b/UserDoc.md
index c80254ba..45e03a20 100644
--- a/UserDoc.md
+++ b/UserDoc.md
@@ -24,6 +24,7 @@ Advanced topics:
 -   Creating custom NetVMs
 -   Creating custom ProxyVMs
 -   [How to copy files to Dom0?](/wiki/CopyToDomZero)
+-   [​Extend root.img size](https://groups.google.com/group/qubes-devel/msg/9d1ac581236ca9b4)
 
 Command-line tools reference: