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+Low-level RPC changes
+---------------------
+
+- Error codes have been updated to be more accurate for the following error cases (#18466):
+  - `signmessage` now returns RPC_INVALID_ADDRESS_OR_KEY (-5) if the
+    passed address is invalid. Previously returned RPC_TYPE_ERROR (-3).
+  - `verifymessage` now returns RPC_INVALID_ADDRESS_OR_KEY (-5) if the
+    passed address is invalid. Previously returned RPC_TYPE_ERROR (-3).
+  - `verifymessage` now returns RPC_TYPE_ERROR (-3) if the passed signature
+    is malformed. Previously returned RPC_INVALID_ADDRESS_OR_KEY (-5).