diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7747ffdaedb30b08d970e91af3b2dc9cc4bfbb9b..3a5c93c594d515a9ab83d42e5010169235a50fdd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -49,6 +49,8 @@ Coq 8.13 is no longer supported.
   `map_to_list`. (by Dorian Lesbre).
 - Make `persistently_True` a bi-entailment.
 - Make `BiLaterContractive` a class instead of a notation.
+- Make projections of `Bupd`/`Fupd`/`InternalEq`/`Plainly` operational type
+  classes `Typeclasses Opaque`.
 
 **Changes in `proofmode`:**