wallet: mark -walletrbf startup option as deprecated

diff --git a/src/wallet/init.cpp b/src/wallet/init.cpp
index ccd82e7a..d21da2a5 100644
--- a/src/wallet/init.cpp
+++ b/src/wallet/init.cpp
@@ -74,7 +74,7 @@ void WalletInit::AddWalletOptions(ArgsManager& argsman) const
 #if HAVE_SYSTEM
     argsman.AddArg("-walletnotify=<cmd>", "Execute command when a wallet transaction changes. %s in cmd is replaced by TxID, %w is replaced by wallet name, %b is replaced by the hash of the block including the transaction (set to 'unconfirmed' if the transaction is not included) and %h is replaced by the block height (-1 if not included). %w is not currently implemented on windows. On systems where %w is supported, it should NOT be quoted because this would break shell escaping used to invoke the command.", ArgsManager::ALLOW_ANY, OptionsCategory::WALLET);
 #endif
-    argsman.AddArg("-walletrbf", strprintf("Send transactions with full-RBF opt-in enabled (RPC only, default: %u)", DEFAULT_WALLET_RBF), ArgsManager::ALLOW_ANY, OptionsCategory::WALLET);
+    argsman.AddArg("-walletrbf", strprintf("(DEPRECATED) Send transactions with full-RBF opt-in enabled (RPC only, default: %u)", DEFAULT_WALLET_RBF), ArgsManager::ALLOW_ANY, OptionsCategory::WALLET);
 
     argsman.AddArg("-unsafesqlitesync", "Set SQLite synchronous=OFF to disable waiting for the database to sync to disk. This is unsafe and can cause data loss and corruption. This option is only used by tests to improve their performance (default: false)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::WALLET_DEBUG_TEST);
 
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 7cfe6102..ea261bd2 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -3102,7 +3102,11 @@ bool CWallet::LoadWalletArgs(std::shared_ptr<CWallet> wallet, const WalletContex
 
     wallet->m_confirm_target = args.GetIntArg("-txconfirmtarget", DEFAULT_TX_CONFIRM_TARGET);
     wallet->m_spend_zero_conf_change = args.GetBoolArg("-spendzeroconfchange", DEFAULT_SPEND_ZEROCONF_CHANGE);
-    wallet->m_signal_rbf = args.GetBoolArg("-walletrbf", DEFAULT_WALLET_RBF);
+    wallet->m_signal_rbf = DEFAULT_WALLET_RBF;
+    if (args.IsArgSet("-walletrbf")) {
+        warnings.push_back(_("-walletrbf is deprecated and will be fully removed in the next release."));
+        wallet->m_signal_rbf = args.GetBoolArg("-walletrbf").value();
+    }
 
     wallet->m_keypool_size = std::max(args.GetIntArg("-keypool", DEFAULT_KEYPOOL_SIZE), int64_t{1});
     wallet->m_notify_tx_changed_script = args.GetArg("-walletnotify", "");
diff --git a/test/functional/test_framework/wallet_util.py b/test/functional/test_framework/wallet_util.py
index 12251530..18095a3b 100755
--- a/test/functional/test_framework/wallet_util.py
+++ b/test/functional/test_framework/wallet_util.py
@@ -24,6 +24,8 @@ from test_framework.script_util import (
     script_to_p2sh_script,
 )
 
+WALLETRBF_DEPRECATION_WARNING = "Warning: -walletrbf is deprecated and will be fully removed in the next release."
+
 Key = namedtuple('Key', ['privkey',
                          'pubkey',
                          'p2pkh_script',
diff --git a/test/functional/wallet_backwards_compatibility.py b/test/functional/wallet_backwards_compatibility.py
index f00f2958..b2a74893 100755
--- a/test/functional/wallet_backwards_compatibility.py
+++ b/test/functional/wallet_backwards_compatibility.py
@@ -28,6 +28,7 @@ from test_framework.util import (
     assert_greater_than,
     assert_raises_rpc_error,
 )
+from test_framework.wallet_util import WALLETRBF_DEPRECATION_WARNING
 
 LAST_KEYPOOL_INDEX = 9 # Index of the last derived address with the keypool size of 10
 
@@ -349,9 +350,7 @@ class BackwardsCompatibilityTest(BitcoinTestFramework):
 
             # Restore the wallet to master
             load_res = node_master.restorewallet(wallet_name, backup_path)
-
-            # There should be no warnings
-            assert "warnings" not in load_res
+            assert_equal(load_res["warnings"], [WALLETRBF_DEPRECATION_WARNING[9:]])
 
             wallet = node_master.get_wallet_rpc(wallet_name)
             info = wallet.getaddressinfo(address)
diff --git a/test/functional/wallet_bumpfee.py b/test/functional/wallet_bumpfee.py
index 961f1a14..992f63ad 100755
--- a/test/functional/wallet_bumpfee.py
+++ b/test/functional/wallet_bumpfee.py
@@ -32,6 +32,7 @@ from test_framework.util import (
     find_vout_for_address,
 )
 from test_framework.wallet import MiniWallet
+from test_framework.wallet_util import WALLETRBF_DEPRECATION_WARNING
 
 
 WALLET_PASSPHRASE = "test"
@@ -116,6 +117,8 @@ class BumpFeeTest(BitcoinTestFramework):
         test_feerate_checks_replaced_outputs(self, rbf_node, peer_node)
         test_bumpfee_with_feerate_ignores_walletincrementalrelayfee(self, rbf_node, peer_node)
 
+        self.restart_node(1, [], expected_stderr=WALLETRBF_DEPRECATION_WARNING)
+
     def test_invalid_parameters(self, rbf_node, peer_node, dest_address):
         self.log.info('Test invalid parameters')
         rbfid = spend_one_input(rbf_node, dest_address)
@@ -460,7 +463,7 @@ def test_bumpfee_with_abandoned_descendant_succeeds(self, rbf_node, rbf_node_add
     assert bumped_result['txid'] in rbf_node.getrawmempool()
     assert parent_id not in rbf_node.getrawmempool()
     # Cleanup
-    self.restart_node(1, self.extra_args[1])
+    self.restart_node(1, self.extra_args[1], expected_stderr=WALLETRBF_DEPRECATION_WARNING)
     rbf_node.walletpassphrase(WALLET_PASSPHRASE, WALLET_PASSPHRASE_TIMEOUT)
     self.connect_nodes(1, 0)
     self.clear_mempool()
@@ -535,11 +538,11 @@ def test_maxtxfee_fails(self, rbf_node, dest_address):
     # size of bumped transaction (p2wpkh, 1 input, 2 outputs): 141 vbytes
     # expected bump fee of 141 vbytes * 0.00200000 BTC / 1000 vbytes = 0.00002820 BTC
     # which exceeds maxtxfee and is expected to raise
-    self.restart_node(1, ['-maxtxfee=0.000025'] + self.extra_args[1])
+    self.restart_node(1, ['-maxtxfee=0.000025'] + self.extra_args[1], expected_stderr=WALLETRBF_DEPRECATION_WARNING)
     rbf_node.walletpassphrase(WALLET_PASSPHRASE, WALLET_PASSPHRASE_TIMEOUT)
     rbfid = spend_one_input(rbf_node, dest_address)
     assert_raises_rpc_error(-4, "Unable to create transaction. Fee exceeds maximum configured by user (e.g. -maxtxfee, maxfeerate)", rbf_node.bumpfee, rbfid)
-    self.restart_node(1, self.extra_args[1])
+    self.restart_node(1, self.extra_args[1], expected_stderr=WALLETRBF_DEPRECATION_WARNING)
     rbf_node.walletpassphrase(WALLET_PASSPHRASE, WALLET_PASSPHRASE_TIMEOUT)
     self.connect_nodes(1, 0)
     self.clear_mempool()
diff --git a/test/functional/wallet_listtransactions.py b/test/functional/wallet_listtransactions.py
index 93e8a45b..d2bdd9b4 100755
--- a/test/functional/wallet_listtransactions.py
+++ b/test/functional/wallet_listtransactions.py
@@ -23,7 +23,7 @@ from test_framework.util import (
     assert_raises_rpc_error,
     find_vout_for_address,
 )
-from test_framework.wallet_util import get_generate_key
+from test_framework.wallet_util import get_generate_key, WALLETRBF_DEPRECATION_WARNING
 
 
 class ListTransactionsTest(BitcoinTestFramework):
@@ -104,6 +104,9 @@ class ListTransactionsTest(BitcoinTestFramework):
         self.test_op_return()
         self.test_from_me_status_change()
 
+        for index, _ in enumerate(self.nodes):
+            self.stop_node(index, expected_stderr=WALLETRBF_DEPRECATION_WARNING)
+
     def run_rbf_opt_in_test(self):
         """Test the opt-in-rbf flag for sent and received transactions."""