diff --git a/pending_changelog/3259-no-downgrade.txt b/pending_changelog/3259-no-downgrade.txt
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+# Backwards Compatibility
+ * Downgrading after using `ChannelManager`'s
+   `unsafe_manual_funding_transaction_generated` may cause deserialization of
+   `ChannelManager` to fail with an `Err` (#3259).