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+### Mempool
+
+mempoolfullrbf=1 behaviour has been the default since v28 and the argument has
+been removed since v29 subsequently. The `getmempoolinfo` RPC stops returning the
+deprecated `fullrbf` key in the response unless the user requests it via the
+`-deprecatedrpc=fullrbf` node argument.
+
+Also, the `bip125-replaceable` key is removed from the mempool RPCs
+responses (because it, too, has been deprecated since v29) unless the user
+requests it via `-deprecatedrpc=bip125` node argument. Affected mempool RPCs
+are `getrawmempool`, `getmempoolancestors`, `getmempooldescendants`, and
+`getmempoolentry`.