diff --git a/README.adoc b/README.adoc
index 5c2065c..891917c 100644
--- a/README.adoc
+++ b/README.adoc
@@ -16,6 +16,10 @@
 *mastorss* reads RSS feeds and posts the items via the Mastodon API. Does not
 support Atom at the moment.
 
+[IMPORTANT]
+The branch `master` has been renamed to `main`. If you have cloned this repo
+before 2019-12-28, please update your git settings accordingly.
+
 == Install
 
 === Dependencies