--- a/README	Thu May 18 22:25:43 2017 +0200
+++ b/README	Thu May 18 23:58:19 2017 +0200
@@ -125,6 +125,7 @@
  - obshashrange-cache: update incrementally in the (common) case of a
    transaction not affecting existing range,
  - obshashrange-cache: keep the cache warm after each transaction,
+ - topic: now requires Mercurial 4.0 or above,
  - stack: now display if current revision is in bad state (issue5533),
  - stack: fix json output to be valid json.