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diff --git a/docs/users_guide/8.12.1-notes.rst b/docs/users_guide/8.12.1-notes.rst
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+++ b/docs/users_guide/8.12.1-notes.rst
@@ -89,6 +89,13 @@ Language
This change prepares the way for `Quick Look impredicativity
<https://gitlab.haskell.org/ghc/ghc/issues/18126>`_.
+* GHC now implements simplified subsumption, as described in `GHC Proposal #287 <https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0287-simplify-subsumption.rst>`__.
+ This change simplifies the type system, and prevents the possiblity of GHC
+ silently changing the semantics of user programs, but it does mean that some libraries
+ may need eta-expansion to typecheck. More info here: :ref:`simple-subsumption`.
+
+ This change also prepares the way for Quick Look impredicativity.
+
* GHC now allows users to manually define the specificity of type variable
binders. By marking a variable with braces ``{tyvar}`` or ``{tyvar :: kind}``,
it becomes inferred despite appearing in a type signature. This feature