diff --git a/src/bench/block_assemble.cpp b/src/bench/block_assemble.cpp
index 702f2c09366..297465be80f 100644
--- a/src/bench/block_assemble.cpp
+++ b/src/bench/block_assemble.cpp
@@ -30,7 +30,6 @@ static void AssembleBlock(benchmark::Bench& bench)
     witness.stack.push_back(WITNESS_STACK_ELEM_OP_TRUE);
     BlockAssembler::Options options;
     options.coinbase_output_script = P2WSH_OP_TRUE;
-    options.include_dummy_extranonce = true;
 
     // Collect some loose transactions that spend the coinbases of our mined blocks
     constexpr size_t NUM_BLOCKS{200};
diff --git a/src/interfaces/mining.h b/src/interfaces/mining.h
index f4c42e204a7..943d34e75d9 100644
--- a/src/interfaces/mining.h
+++ b/src/interfaces/mining.h
@@ -34,7 +34,8 @@ public:
     virtual ~BlockTemplate() = default;
 
     virtual CBlockHeader getBlockHeader() = 0;
-    // Block contains a dummy coinbase transaction that should not be used.
+    // Block contains a dummy coinbase transaction that should not be used and
+    // it may not match a transaction constructed from getCoinbaseTx().
     virtual CBlock getBlock() = 0;
 
     // Fees per transaction, not including coinbase transaction.
@@ -64,6 +65,10 @@ public:
      * @note unlike the submitblock RPC, this method does NOT add the
      *       coinbase witness automatically.
      *
+     * @note for heights <= 16, the BIP34 height push in getCoinbaseTx().script_sig_prefix
+     *       is only one byte long, so the coinbase scriptSig needs at least
+     *       one additional byte of data to avoid bad-cb-length.
+     *
      * @returns if the block was processed, does not necessarily indicate validity.
      *
      * @note Returns true if the block is already known, which can happen if
diff --git a/src/kernel/chainparams.cpp b/src/kernel/chainparams.cpp
index 02c7ae9d220..969a838cd22 100644
--- a/src/kernel/chainparams.cpp
+++ b/src/kernel/chainparams.cpp
@@ -607,9 +607,9 @@ public:
         m_assumeutxo_data = {
             {   // For use by unit tests
                 .height = 110,
-                .hash_serialized = AssumeutxoHash{uint256{"b952555c8ab81fec46f3d4253b7af256d766ceb39fb7752b9d18cdf4a0141327"}},
+                .hash_serialized = AssumeutxoHash{uint256{"86e9a1205b418b16dde3a18a78c730e30137e28466bda5dbf6b33ab8fc05447c"}},
                 .m_chain_tx_count = 111,
-                .blockhash = uint256{"6affe030b7965ab538f820a56ef56c8149b7dc1d1c144af57113be080db7c397"},
+                .blockhash = uint256{"135eec25a6fb277884e5824e7aa7d052c4868161c99a5122170b5266f86c273d"},
             },
             {
                 // For use by fuzz target src/test/fuzz/utxo_snapshot.cpp
@@ -621,9 +621,9 @@ public:
             {
                 // For use by test/functional/feature_assumeutxo.py and test/functional/tool_bitcoin_chainstate.py
                 .height = 299,
-                .hash_serialized = AssumeutxoHash{uint256{"d2b051ff5e8eef46520350776f4100dd710a63447a8e01d917e92e79751a63e2"}},
+                .hash_serialized = AssumeutxoHash{uint256{"106b2c56233e378a824cf0d5ff2be42ed32c72f1605c9be288d00942908a40ac"}},
                 .m_chain_tx_count = 334,
-                .blockhash = uint256{"7cc695046fec709f8c9394b6f928f81e81fd3ac20977bb68760fa1faa7916ea2"},
+                .blockhash = uint256{"0c552ced4721c249a389eb9b08cb8da261cd46f0e7b5f9d064d48f3113406853"},
             },
         };
 
diff --git a/src/node/miner.cpp b/src/node/miner.cpp
index 836b828b5c4..7fc19deeb79 100644
--- a/src/node/miner.cpp
+++ b/src/node/miner.cpp
@@ -184,14 +184,18 @@ std::unique_ptr<CBlockTemplate> BlockAssembler::CreateNewBlock()
     // increasing its length would reduce the space they can use and may break
     // existing clients.
     coinbaseTx.vin[0].scriptSig = CScript() << nHeight;
-    if (m_options.include_dummy_extranonce) {
+    // Set script_sig_prefix here, so IPC mining clients are not affected by
+    // the optional scriptSig padding below. They provide their own extraNonce,
+    // and in a typical setup a pool name or realistic extraNonce already makes
+    // the scriptSig long enough.
+    coinbase_tx.script_sig_prefix = coinbaseTx.vin[0].scriptSig;
+    if (nHeight <= 16) {
         // For blocks at heights <= 16, the BIP34-encoded height alone is only
         // one byte. Consensus requires coinbase scriptSigs to be at least two
-        // bytes long (bad-cb-length), so tests and regtest include a dummy
-        // extraNonce (OP_0)
+        // bytes long (bad-cb-length), so an OP_0 is always appended at those
+        // heights.
         coinbaseTx.vin[0].scriptSig << OP_0;
     }
-    coinbase_tx.script_sig_prefix = coinbaseTx.vin[0].scriptSig;
     Assert(nHeight > 0);
     coinbaseTx.nLockTime = static_cast<uint32_t>(nHeight - 1);
     coinbase_tx.lock_time = coinbaseTx.nLockTime;
@@ -221,7 +225,6 @@ std::unique_ptr<CBlockTemplate> BlockAssembler::CreateNewBlock()
     pblock->nNonce         = 0;
 
     if (m_options.test_block_validity) {
-        // if nHeight <= 16, and include_dummy_extranonce=false this will fail due to bad-cb-length.
         if (BlockValidationState state{TestBlockValidity(m_chainstate, *pblock, /*check_pow=*/false, /*check_merkle_root=*/false)}; !state.IsValid()) {
             throw std::runtime_error(strprintf("TestBlockValidity failed: %s", state.ToString()));
         }
diff --git a/src/node/types.h b/src/node/types.h
index 01e74528e06..d228fa41db6 100644
--- a/src/node/types.h
+++ b/src/node/types.h
@@ -72,10 +72,6 @@ struct BlockCreateOptions {
      * coinbase_max_additional_weight and coinbase_output_max_additional_sigops.
      */
     CScript coinbase_output_script{CScript() << OP_TRUE};
-    /**
-     * Whether to include an OP_0 as a dummy extraNonce in the template's coinbase
-     */
-    bool include_dummy_extranonce{false};
 };
 
 struct BlockWaitOptions {
@@ -125,7 +121,9 @@ struct CoinbaseTx {
      * Prefix which needs to be placed at the beginning of the scriptSig.
      * Clients may append extra data to this as long as the overall scriptSig
      * size is 100 bytes or less, to avoid the block being rejected with
-     * "bad-cb-length" error.
+     * "bad-cb-length" error. At heights <= 16 the BIP 34 height push is only
+     * one byte long, so clients must append at least one additional byte to
+     * meet the consensus minimum scriptSig length of two bytes.
      *
      * Currently with BIP 34, the prefix is guaranteed to be less than 8 bytes,
      * but future soft forks could require longer prefixes.
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index dcf5ee26457..223569fdafe 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -165,7 +165,7 @@ static UniValue generateBlocks(ChainstateManager& chainman, Mining& miner, const
 {
     UniValue blockHashes(UniValue::VARR);
     while (nGenerate > 0 && !chainman.m_interrupt) {
-        std::unique_ptr<BlockTemplate> block_template(miner.createNewBlock({ .coinbase_output_script = coinbase_output_script, .include_dummy_extranonce = true }, /*cooldown=*/false));
+        std::unique_ptr<BlockTemplate> block_template(miner.createNewBlock({ .coinbase_output_script = coinbase_output_script }, /*cooldown=*/false));
         CHECK_NONFATAL(block_template);
 
         std::shared_ptr<const CBlock> block_out;
@@ -377,7 +377,7 @@ static RPCMethod generateblock()
     {
         LOCK(chainman.GetMutex());
         {
-            std::unique_ptr<BlockTemplate> block_template{miner.createNewBlock({.use_mempool = false, .coinbase_output_script = coinbase_output_script, .include_dummy_extranonce = true}, /*cooldown=*/false)};
+            std::unique_ptr<BlockTemplate> block_template{miner.createNewBlock({.use_mempool = false, .coinbase_output_script = coinbase_output_script}, /*cooldown=*/false)};
             CHECK_NONFATAL(block_template);
 
             block = block_template->getBlock();
@@ -875,7 +875,7 @@ static RPCMethod getblocktemplate()
         // a delay to each getblocktemplate call. This differs from typical
         // long-lived IPC usage, where the overhead is paid only when creating
         // the initial template.
-        block_template = miner.createNewBlock({.include_dummy_extranonce = true}, /*cooldown=*/false);
+        block_template = miner.createNewBlock({}, /*cooldown=*/false);
         CHECK_NONFATAL(block_template);
 
 
diff --git a/src/test/blockfilter_index_tests.cpp b/src/test/blockfilter_index_tests.cpp
index 10e4ffa4b08..b77942f741d 100644
--- a/src/test/blockfilter_index_tests.cpp
+++ b/src/test/blockfilter_index_tests.cpp
@@ -71,7 +71,6 @@ CBlock BuildChainTestingSetup::CreateBlock(const CBlockIndex* prev,
 {
     BlockAssembler::Options options;
     options.coinbase_output_script = scriptPubKey;
-    options.include_dummy_extranonce = true;
     std::unique_ptr<CBlockTemplate> pblocktemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock();
     CBlock& block = pblocktemplate->block;
     block.hashPrevBlock = prev->GetBlockHash();
diff --git a/src/test/fuzz/cmpctblock.cpp b/src/test/fuzz/cmpctblock.cpp
index 6af9883a2e9..85e3bedfe92 100644
--- a/src/test/fuzz/cmpctblock.cpp
+++ b/src/test/fuzz/cmpctblock.cpp
@@ -123,7 +123,6 @@ void ResetChainmanAndMempool(TestingSetup& setup)
 
     node::BlockAssembler::Options options;
     options.coinbase_output_script = P2WSH_OP_TRUE;
-    options.include_dummy_extranonce = true;
 
     g_mature_coinbase.clear();
 
diff --git a/src/test/fuzz/package_eval.cpp b/src/test/fuzz/package_eval.cpp
index 93cd8ad6bbd..1cc2caa396e 100644
--- a/src/test/fuzz/package_eval.cpp
+++ b/src/test/fuzz/package_eval.cpp
@@ -46,7 +46,6 @@ void initialize_tx_pool()
 
     BlockAssembler::Options options;
     options.coinbase_output_script = P2WSH_EMPTY;
-    options.include_dummy_extranonce = true;
 
     for (int i = 0; i < 2 * COINBASE_MATURITY; ++i) {
         COutPoint prevout{MineBlock(g_setup->m_node, options)};
diff --git a/src/test/fuzz/process_message.cpp b/src/test/fuzz/process_message.cpp
index 5f54857ea5f..d8a91d7f90a 100644
--- a/src/test/fuzz/process_message.cpp
+++ b/src/test/fuzz/process_message.cpp
@@ -43,7 +43,6 @@ void ResetChainman(TestingSetup& setup)
     setup.LoadVerifyActivateChainstate();
     for (int i = 0; i < 2 * COINBASE_MATURITY; i++) {
         node::BlockAssembler::Options options;
-        options.include_dummy_extranonce = true;
         MineBlock(setup.m_node, options);
     }
 }
diff --git a/src/test/fuzz/process_messages.cpp b/src/test/fuzz/process_messages.cpp
index 9f33b0df24b..314388fac07 100644
--- a/src/test/fuzz/process_messages.cpp
+++ b/src/test/fuzz/process_messages.cpp
@@ -37,7 +37,6 @@ void ResetChainman(TestingSetup& setup)
     setup.m_make_chainman();
     setup.LoadVerifyActivateChainstate();
     node::BlockAssembler::Options options;
-    options.include_dummy_extranonce = true;
     for (int i = 0; i < 2 * COINBASE_MATURITY; i++) {
         MineBlock(setup.m_node, options);
     }
diff --git a/src/test/fuzz/tx_pool.cpp b/src/test/fuzz/tx_pool.cpp
index bb15552723a..f70dd710b35 100644
--- a/src/test/fuzz/tx_pool.cpp
+++ b/src/test/fuzz/tx_pool.cpp
@@ -48,7 +48,6 @@ void initialize_tx_pool()
 
     BlockAssembler::Options options;
     options.coinbase_output_script = P2WSH_OP_TRUE;
-    options.include_dummy_extranonce = true;
 
     for (int i = 0; i < 2 * COINBASE_MATURITY; ++i) {
         COutPoint prevout{MineBlock(g_setup->m_node, options)};
@@ -98,7 +97,6 @@ void Finish(FuzzedDataProvider& fuzzed_data_provider, MockedTxPool& tx_pool, Cha
         BlockAssembler::Options options;
         options.nBlockMaxWeight = fuzzed_data_provider.ConsumeIntegralInRange(0U, MAX_BLOCK_WEIGHT);
         options.blockMinFeeRate = CFeeRate{ConsumeMoney(fuzzed_data_provider, /*max=*/COIN)};
-        options.include_dummy_extranonce = true;
         auto assembler = BlockAssembler{chainstate, &tx_pool, options};
         auto block_template = assembler.CreateNewBlock();
         Assert(block_template->block.vtx.size() >= 1);
diff --git a/src/test/fuzz/utxo_total_supply.cpp b/src/test/fuzz/utxo_total_supply.cpp
index 1275fd45c43..b281f20028e 100644
--- a/src/test/fuzz/utxo_total_supply.cpp
+++ b/src/test/fuzz/utxo_total_supply.cpp
@@ -46,7 +46,6 @@ FUZZ_TARGET(utxo_total_supply)
     };
     BlockAssembler::Options options;
     options.coinbase_output_script = CScript() << OP_FALSE;
-    options.include_dummy_extranonce = true;
     const auto PrepareNextBlock = [&]() {
         // Use OP_FALSE to avoid BIP30 check from hitting early
         auto block = PrepareBlock(node, options);
@@ -107,8 +106,12 @@ FUZZ_TARGET(utxo_total_supply)
     // Assuming that the fuzzer will mine relatively short chains (less than 200 blocks), we want the duplicate coinbase to be not too high.
     // Up to 300 seems reasonable.
     int64_t duplicate_coinbase_height = fuzzed_data_provider.ConsumeIntegralInRange(0, 300);
-    // Always pad with OP_0 at the end to avoid bad-cb-length error
-    const CScript duplicate_coinbase_script = CScript() << duplicate_coinbase_height << OP_0;
+    // Avoid bad-cb-length error at heights <= 16. Pad the BIP34-encoded height
+    // with OP_0 to satisfy the minimum 2-byte coinbase scriptSig length.
+    CScript duplicate_coinbase_script = CScript() << duplicate_coinbase_height;
+    if (duplicate_coinbase_height <= 16) {
+        duplicate_coinbase_script << OP_0;
+    }
     // Mine the first block with this duplicate
     current_block = PrepareNextBlock();
     StoreLastTxo();
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index 6b4e85a59e4..124ef08500c 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -117,7 +117,6 @@ void MinerTestingSetup::TestPackageSelection(const CScript& scriptPubKey, const
     auto mining{MakeMining()};
     BlockAssembler::Options options;
     options.coinbase_output_script = scriptPubKey;
-    options.include_dummy_extranonce = true;
 
     LOCK(tx_mempool.cs);
     BOOST_CHECK(tx_mempool.size() == 0);
@@ -336,7 +335,6 @@ void MinerTestingSetup::TestBasicMining(const CScript& scriptPubKey, const std::
 
     BlockAssembler::Options options;
     options.coinbase_output_script = scriptPubKey;
-    options.include_dummy_extranonce = true;
 
     {
         CTxMemPool& tx_mempool{MakeMempool()};
@@ -663,7 +661,6 @@ void MinerTestingSetup::TestPrioritisedMining(const CScript& scriptPubKey, const
 
     BlockAssembler::Options options;
     options.coinbase_output_script = scriptPubKey;
-    options.include_dummy_extranonce = true;
 
     CTxMemPool& tx_mempool{MakeMempool()};
     LOCK(tx_mempool.cs);
@@ -753,7 +750,6 @@ BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
     CScript scriptPubKey = CScript() << "04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f"_hex << OP_CHECKSIG;
     BlockAssembler::Options options;
     options.coinbase_output_script = scriptPubKey;
-    options.include_dummy_extranonce = true;
 
     // Create and check a simple template
     std::unique_ptr<BlockTemplate> block_template = mining->createNewBlock(options, /*cooldown=*/false);
diff --git a/src/test/peerman_tests.cpp b/src/test/peerman_tests.cpp
index e391e8b9c3f..36a66b14eb5 100644
--- a/src/test/peerman_tests.cpp
+++ b/src/test/peerman_tests.cpp
@@ -20,7 +20,6 @@ static void mineBlock(const node::NodeContext& node, std::chrono::seconds block_
 {
     auto curr_time = GetTime<std::chrono::seconds>();
     node::BlockAssembler::Options options;
-    options.include_dummy_extranonce = true;
     SetMockTime(block_time); // update time so the block is created with it
     CBlock block = node::BlockAssembler{node.chainman->ActiveChainstate(), nullptr, options}.CreateNewBlock()->block;
     while (!CheckProofOfWork(block.GetHash(), block.nBits, node.chainman->GetConsensus())) ++block.nNonce;
diff --git a/src/test/testnet4_miner_tests.cpp b/src/test/testnet4_miner_tests.cpp
index 1bfc19db270..c501b4eb086 100644
--- a/src/test/testnet4_miner_tests.cpp
+++ b/src/test/testnet4_miner_tests.cpp
@@ -36,7 +36,6 @@ BOOST_AUTO_TEST_CASE(MiningInterface)
     BOOST_REQUIRE(mining);
 
     BlockAssembler::Options options;
-    options.include_dummy_extranonce = true;
     std::unique_ptr<BlockTemplate> block_template;
 
     // Set node time a few minutes past the testnet4 genesis block
diff --git a/src/test/util/mining.cpp b/src/test/util/mining.cpp
index c4823bce351..05f1be77ee2 100644
--- a/src/test/util/mining.cpp
+++ b/src/test/util/mining.cpp
@@ -29,7 +29,6 @@ COutPoint generatetoaddress(const NodeContext& node, const std::string& address)
     assert(IsValidDestination(dest));
     BlockAssembler::Options assembler_options;
     assembler_options.coinbase_output_script = GetScriptForDestination(dest);
-    assembler_options.include_dummy_extranonce = true;
 
     return MineBlock(node, assembler_options);
 }
@@ -140,7 +139,6 @@ std::shared_ptr<CBlock> PrepareBlock(const NodeContext& node, const CScript& coi
 {
     BlockAssembler::Options assembler_options;
     assembler_options.coinbase_output_script = coinbase_scriptPubKey;
-    assembler_options.include_dummy_extranonce = true;
     ApplyArgsManOptions(*node.args, assembler_options);
     return PrepareBlock(node, assembler_options);
 }
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 39c691c3364..f924a0e8c7d 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -390,7 +390,7 @@ TestChain100Setup::TestChain100Setup(
         LOCK(::cs_main);
         assert(
             m_node.chainman->ActiveChain().Tip()->GetBlockHash().ToString() ==
-            "0c8c5f79505775a0f6aed6aca2350718ceb9c6f2c878667864d5c7a6d8ffa2a6");
+            "0ee6e270d6594249e548110619f7bd690695beb219b915da4a2e84e2b61ed60f");
     }
 }
 
@@ -412,7 +412,6 @@ CBlock TestChain100Setup::CreateBlock(
 {
     BlockAssembler::Options options;
     options.coinbase_output_script = scriptPubKey;
-    options.include_dummy_extranonce = true;
     CBlock block = BlockAssembler{chainstate, nullptr, options}.CreateNewBlock()->block;
 
     Assert(block.vtx.size() == 1);
diff --git a/src/test/validation_block_tests.cpp b/src/test/validation_block_tests.cpp
index 083a32da963..e1f90477fc4 100644
--- a/src/test/validation_block_tests.cpp
+++ b/src/test/validation_block_tests.cpp
@@ -69,7 +69,6 @@ std::shared_ptr<CBlock> MinerTestingSetup::Block(const uint256& prev_hash)
 
     BlockAssembler::Options options;
     options.coinbase_output_script = CScript{} << i++ << OP_TRUE;
-    options.include_dummy_extranonce = true;
     auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock();
     auto pblock = std::make_shared<CBlock>(ptemplate->block);
     pblock->hashPrevBlock = prev_hash;
@@ -338,7 +337,6 @@ BOOST_AUTO_TEST_CASE(witness_commitment_index)
     pubKey << 1 << OP_TRUE;
     BlockAssembler::Options options;
     options.coinbase_output_script = pubKey;
-    options.include_dummy_extranonce = true;
     auto ptemplate = BlockAssembler{m_node.chainman->ActiveChainstate(), m_node.mempool.get(), options}.CreateNewBlock();
     CBlock pblock = ptemplate->block;
 
diff --git a/src/test/validation_tests.cpp b/src/test/validation_tests.cpp
index b1e204f1741..268529fd802 100644
--- a/src/test/validation_tests.cpp
+++ b/src/test/validation_tests.cpp
@@ -142,11 +142,11 @@ BOOST_AUTO_TEST_CASE(test_assumeutxo)
     }
 
     const auto out110 = *params->AssumeutxoForHeight(110);
-    BOOST_CHECK_EQUAL(out110.hash_serialized.ToString(), "b952555c8ab81fec46f3d4253b7af256d766ceb39fb7752b9d18cdf4a0141327");
+    BOOST_CHECK_EQUAL(out110.hash_serialized.ToString(), "86e9a1205b418b16dde3a18a78c730e30137e28466bda5dbf6b33ab8fc05447c");
     BOOST_CHECK_EQUAL(out110.m_chain_tx_count, 111U);
 
-    const auto out110_2 = *params->AssumeutxoForBlockhash(uint256{"6affe030b7965ab538f820a56ef56c8149b7dc1d1c144af57113be080db7c397"});
-    BOOST_CHECK_EQUAL(out110_2.hash_serialized.ToString(), "b952555c8ab81fec46f3d4253b7af256d766ceb39fb7752b9d18cdf4a0141327");
+    const auto out110_2 = *params->AssumeutxoForBlockhash(uint256{"135eec25a6fb277884e5824e7aa7d052c4868161c99a5122170b5266f86c273d"});
+    BOOST_CHECK_EQUAL(out110_2.hash_serialized.ToString(), "86e9a1205b418b16dde3a18a78c730e30137e28466bda5dbf6b33ab8fc05447c");
     BOOST_CHECK_EQUAL(out110_2.m_chain_tx_count, 111U);
 }
 
diff --git a/test/functional/feature_assumeutxo.py b/test/functional/feature_assumeutxo.py
index ae130ee2035..8727a9925ec 100755
--- a/test/functional/feature_assumeutxo.py
+++ b/test/functional/feature_assumeutxo.py
@@ -139,12 +139,12 @@ class AssumeutxoTest(BitcoinTestFramework):
         self.log.info("  - snapshot file with alternated but parsable UTXO data results in different hash")
         cases = [
             # (content, offset, wrong_hash, custom_message)
-            [b"\xff" * 32, 0, "77874d48d932a5cb7a7f770696f5224ff05746fdcf732a58270b45da0f665934", None],  # wrong outpoint hash
-            [(2).to_bytes(1, "little"), 32, None, "Bad snapshot format or truncated snapshot after deserializing 1 coins."],  # wrong txid coins count
+            [b"\xff" * 32, 0, "43bb0fcc50f3789d50ce41891810bbc571d549a32e2bbaabfc036f73ae2a23f9", None],  # wrong outpoint hash
+            [(2).to_bytes(1, "little"), 32, None, "Bad snapshot data after deserializing 2 coins."],  # wrong txid coins count
             [b"\xfd\xff\xff", 32, None, "Mismatch in coins count in snapshot metadata and actual snapshot data"],  # txid coins count exceeds coins left
-            [b"\x01", 33, "9f562925721e4f97e6fde5b590dbfede51e2204a68639525062ad064545dd0ea", None],  # wrong outpoint index
-            [b"\x82", 34, "161393f07f8ad71760b3910a914f677f2cb166e5bcf5354e50d46b78c0422d15", None],  # wrong coin code VARINT
-            [b"\x80", 34, "e6fae191ef851554467b68acff01ca09ad0a2e48c9b3dfea46cf7d35a7fd0ad0", None],  # another wrong coin code
+            [b"\x01", 33, "0b0e96fd9a556157a68d9e6fe6e2c7562169c730347565ce0725032f824bea34", None],  # wrong outpoint index
+            [b"\x83", 34, "52084c732f760fbcfb804d854815a9145111e93d7c7f3f7bfcb0ade1ea4f6b99", None],  # wrong coin code VARINT
+            [b"\x80", 34, "c1a1308fcf04cbb14fc777467eb5e98e77a921b66eac4ad47877d0b6ed7b15b1", None],  # another wrong coin code
             [b"\x84\x58", 34, None, "Bad snapshot data after deserializing 0 coins"],  # wrong coin case with height 364 and coinbase 0
             [
                 # compressed txout value + scriptpubkey
@@ -163,12 +163,12 @@ class AssumeutxoTest(BitcoinTestFramework):
                 f.write(content)
                 f.write(valid_snapshot_contents[(5 + 2 + 4 + 32 + 8 + offset + len(content)):])
 
-            msg = custom_message if custom_message is not None else f"Bad snapshot content hash: expected d2b051ff5e8eef46520350776f4100dd710a63447a8e01d917e92e79751a63e2, got {wrong_hash}."
+            msg = custom_message if custom_message is not None else f"Bad snapshot content hash: expected 106b2c56233e378a824cf0d5ff2be42ed32c72f1605c9be288d00942908a40ac, got {wrong_hash}."
             expected_error(msg)
 
     def test_headers_not_synced(self, valid_snapshot_path):
         for node in self.nodes[1:]:
-            msg = "Unable to load UTXO snapshot: The base block header (7cc695046fec709f8c9394b6f928f81e81fd3ac20977bb68760fa1faa7916ea2) must appear in the headers chain. Make sure all headers are syncing, and call loadtxoutset again."
+            msg = "Unable to load UTXO snapshot: The base block header (0c552ced4721c249a389eb9b08cb8da261cd46f0e7b5f9d064d48f3113406853) must appear in the headers chain. Make sure all headers are syncing, and call loadtxoutset again."
             assert_raises_rpc_error(-32603, msg, node.loadtxoutset, valid_snapshot_path)
 
     def test_invalid_chainstate_scenarios(self):
@@ -228,7 +228,7 @@ class AssumeutxoTest(BitcoinTestFramework):
             block_hash = node.getblockhash(height)
             node.invalidateblock(block_hash)
             assert_equal(node.getblockcount(), height - 1)
-            msg = "Unable to load UTXO snapshot: The base block header (7cc695046fec709f8c9394b6f928f81e81fd3ac20977bb68760fa1faa7916ea2) is part of an invalid chain."
+            msg = "Unable to load UTXO snapshot: The base block header (0c552ced4721c249a389eb9b08cb8da261cd46f0e7b5f9d064d48f3113406853) is part of an invalid chain."
             assert_raises_rpc_error(-32603, msg, node.loadtxoutset, dump_output_path)
             node.reconsiderblock(block_hash)
 
@@ -469,7 +469,7 @@ class AssumeutxoTest(BitcoinTestFramework):
         def check_dump_output(output):
             assert_equal(
                 output['txoutset_hash'],
-                "d2b051ff5e8eef46520350776f4100dd710a63447a8e01d917e92e79751a63e2")
+                "106b2c56233e378a824cf0d5ff2be42ed32c72f1605c9be288d00942908a40ac")
             assert_equal(output["nchaintx"], blocks[SNAPSHOT_BASE_HEIGHT].chain_tx)
 
         check_dump_output(dump_output)
@@ -499,7 +499,7 @@ class AssumeutxoTest(BitcoinTestFramework):
         dump_output4 = n0.dumptxoutset(path='utxos4.dat', rollback=prev_snap_height)
         assert_equal(
             dump_output4['txoutset_hash'],
-            "45ac2777b6ca96588210e2a4f14b602b41ec37b8b9370673048cc0af434a1ec8")
+            "147d1789e3e29a62e3e15b80078b50603afb5e1e70ea07001c94666afbde38df")
         assert_not_equal(sha256sum_file(dump_output['path']), sha256sum_file(dump_output4['path']))
 
         # Use a hash instead of a height
diff --git a/test/functional/feature_index_prune.py b/test/functional/feature_index_prune.py
index 0654e04f586..ba4907acdcf 100755
--- a/test/functional/feature_index_prune.py
+++ b/test/functional/feature_index_prune.py
@@ -100,7 +100,7 @@ class FeatureIndexPruneTest(BitcoinTestFramework):
                 pruneheight_new = node.pruneblockchain(400)
                 # the prune heights used here and below are magic numbers that are determined by the
                 # thresholds at which block files wrap, so they depend on disk serialization and default block file size.
-                assert_equal(pruneheight_new, 248)
+                assert_equal(pruneheight_new, 249)
 
         self.log.info("check if we can access the tips blockfilter and coinstats when we have pruned some blocks")
         tip = self.nodes[0].getbestblockhash()
@@ -117,8 +117,8 @@ class FeatureIndexPruneTest(BitcoinTestFramework):
             assert node.gettxoutsetinfo(hash_type="muhash", hash_or_height=height_hash)['muhash']
 
         # mine and sync index up to a height that will later be the pruneheight
-        self.generate(self.nodes[0], 51)
-        self.sync_index(height=751)
+        self.generate(self.nodes[0], 54)
+        self.sync_index(height=754)
 
         self.restart_without_indices()
 
@@ -130,12 +130,12 @@ class FeatureIndexPruneTest(BitcoinTestFramework):
             msg = "Querying specific block heights requires coinstatsindex"
             assert_raises_rpc_error(-8, msg, node.gettxoutsetinfo, "muhash", height_hash)
 
-        self.generate(self.nodes[0], 749)
+        self.generate(self.nodes[0], 746)
 
         self.log.info("prune exactly up to the indices best blocks while the indices are disabled")
         for i in range(3):
             pruneheight_2 = self.nodes[i].pruneblockchain(1000)
-            assert_equal(pruneheight_2, 750)
+            assert_equal(pruneheight_2, 753)
             # Restart the nodes again with the indices activated
             self.restart_node(i, extra_args=self.extra_args[i])
 
@@ -195,7 +195,7 @@ class FeatureIndexPruneTest(BitcoinTestFramework):
         for node in self.nodes[:2]:
             with node.assert_debug_log(['limited pruning to height 2489']):
                 pruneheight_new = node.pruneblockchain(2500)
-                assert_equal(pruneheight_new, 2005)
+                assert_equal(pruneheight_new, 2013)
 
         self.log.info("ensure that prune locks don't prevent indices from failing in a reorg scenario")
         with self.nodes[0].assert_debug_log(['basic block filter index prune lock moved back to 2480']):
diff --git a/test/functional/feature_utxo_set_hash.py b/test/functional/feature_utxo_set_hash.py
index 733b1fea185..fb64439ecc5 100755
--- a/test/functional/feature_utxo_set_hash.py
+++ b/test/functional/feature_utxo_set_hash.py
@@ -67,8 +67,8 @@ class UTXOSetHashTest(BitcoinTestFramework):
         assert_equal(finalized[::-1].hex(), node_muhash)
 
         self.log.info("Test deterministic UTXO set hash results")
-        assert_equal(node.gettxoutsetinfo()['hash_serialized_3'], "e0b4c80f2880985fdf1adc331ed0735ac207588f986c91c7c05e8cf5fe6780f0")
-        assert_equal(node.gettxoutsetinfo("muhash")['muhash'], "8739b878f23030ef39a5547edc7b57f88d50fdaaf47314ff0524608deb13067e")
+        assert_equal(node.gettxoutsetinfo()['hash_serialized_3'], "396058cfd7f3b4c05dcdfaf360be9986d859d2c8315082d3aadda6d2d16add25")
+        assert_equal(node.gettxoutsetinfo("muhash")['muhash'], "97f341d4226cb4451dd9da2856759fb97659cfc238a0b8d5452e64af6032bd3d")
 
     def run_test(self):
         self.test_muhash_implementation()
diff --git a/test/functional/interface_ipc_mining.py b/test/functional/interface_ipc_mining.py
index 31ccec63fa8..2740662f1c0 100755
--- a/test/functional/interface_ipc_mining.py
+++ b/test/functional/interface_ipc_mining.py
@@ -7,7 +7,7 @@ import asyncio
 import time
 from contextlib import AsyncExitStack
 from io import BytesIO
-from test_framework.blocktools import NULL_OUTPOINT
+from test_framework.blocktools import NULL_OUTPOINT, script_BIP34_coinbase_height
 from test_framework.messages import (
     MAX_BLOCK_WEIGHT,
     CBlockHeader,
@@ -20,10 +20,6 @@ from test_framework.messages import (
     from_hex,
     msg_headers,
 )
-from test_framework.script import (
-    CScript,
-    CScriptNum,
-)
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import (
     assert_equal,
@@ -67,7 +63,7 @@ class IPCMiningTest(BitcoinTestFramework):
         # as it is being called before knowing whether capnp is available).
         self.capnp_modules = load_capnp_modules(self.config)
 
-    async def build_coinbase_test(self, template, ctx, miniwallet):
+    async def build_coinbase_test(self, template, ctx, miniwallet, extra_nonce=b""):
         self.log.debug("Build coinbase transaction using getCoinbaseTx()")
         assert template is not None
         coinbase_res = await mining_get_coinbase_tx(template, ctx)
@@ -79,11 +75,11 @@ class IPCMiningTest(BitcoinTestFramework):
 
         # Verify there's no dummy extraNonce in the coinbase scriptSig
         current_block_height = self.nodes[0].getchaintips()[0]["height"]
-        expected_scriptsig = CScript([CScriptNum(current_block_height + 1)])
-        assert_equal(coinbase_res.scriptSigPrefix.hex(), expected_scriptsig.hex())
+        bip34_prefix = script_BIP34_coinbase_height(current_block_height + 1, padding=False)
+        assert_equal(coinbase_res.scriptSigPrefix, bip34_prefix)
 
         # Typically a mining pool appends its name and an extraNonce
-        coinbase_tx.vin[0].scriptSig = coinbase_res.scriptSigPrefix
+        coinbase_tx.vin[0].scriptSig = coinbase_res.scriptSigPrefix + extra_nonce
 
         # We currently always provide a coinbase witness, even for empty
         # blocks, but this may change, so always check:
@@ -407,6 +403,50 @@ class IPCMiningTest(BitcoinTestFramework):
 
         asyncio.run(capnp.run(async_routine()))
 
+    def run_low_height_test(self):
+        """Test that IPC createNewBlock() works at low block heights on a
+        clean chain, in particular with regard to bad-cb-length.
+
+        createNewBlock pads the scriptSig with a dummy extranonce to pass
+        its internal CheckBlock(). This dummy is omitted from the
+        getCoinbaseTx() script_sig_prefix field. The client provides its
+        own extraNonce via submitSolution()."""
+        self.log.info("Running low block height test")
+
+        node = self.nodes[0]
+        self.stop_node(0)
+        # Clear chain data to start from genesis
+        self.cleanup_folder(node.chain_path)
+        node.start()
+        node.wait_for_rpc_connection()
+        assert_equal(node.getblockcount(), 0)
+
+        miniwallet = MiniWallet(node)
+
+        async def async_routine():
+            ctx, mining = await make_mining_ctx(self)
+            opts = self.capnp_modules['mining'].BlockCreateOptions()
+
+            # Mine blocks 1-17 to exercise the boundary at height 16, where the
+            # internal scriptSig padding is no longer needed.
+            for height in range(1, 18):
+                async with AsyncExitStack() as stack:
+                    # Disable cooldown to avoid hanging in the IBD loop on a fresh chain
+                    template = await mining_create_block_template(mining, stack, ctx, opts, cooldown=False)
+                    assert template is not None
+                    block = await mining_get_block(template, ctx)
+                    # Heights <= 16 need extra nonce padding.
+                    extra_nonce = b'\xaa\xbb\xcc\xdd' if height <= 16 else b""
+                    coinbase = await self.build_coinbase_test(template, ctx, miniwallet, extra_nonce=extra_nonce)
+                    block.vtx[0] = coinbase
+                    block.hashMerkleRoot = block.calc_merkle_root()
+                    block.solve()
+                    submitted = (await template.submitSolution(ctx, block.nVersion, block.nTime, block.nNonce, coinbase.serialize())).result
+                    assert_equal(submitted, True)
+                    assert_equal(node.getblockcount(), height)
+
+        asyncio.run(capnp.run(async_routine()))
+
     def run_test(self):
         self.miniwallet = MiniWallet(self.nodes[0])
         self.default_block_create_options = self.capnp_modules['mining'].BlockCreateOptions()
@@ -416,6 +456,9 @@ class IPCMiningTest(BitcoinTestFramework):
         self.run_coinbase_and_submission_test()
         self.run_ipc_option_override_test()
 
+        # Needs to run last because it resets the chain.
+        self.run_low_height_test()
+
 
 if __name__ == '__main__':
     IPCMiningTest(__file__).main()
diff --git a/test/functional/rpc_dumptxoutset.py b/test/functional/rpc_dumptxoutset.py
index 80c4bf6fe6a..47568c248e0 100755
--- a/test/functional/rpc_dumptxoutset.py
+++ b/test/functional/rpc_dumptxoutset.py
@@ -68,15 +68,15 @@ class DumptxoutsetTest(BitcoinTestFramework):
         # Blockhash should be deterministic based on mocked time.
         assert_equal(
             out['base_hash'],
-            '6885775faa46290bedfa071f22d0598c93f1d7e01f24607c4dedd69b9baa4a8f')
+            '220aee93f0f5409631f35488898258f0930952bd620063cb4d7d87f7c28a8f50')
 
         # UTXO snapshot hash should be deterministic based on mocked time.
         assert_equal(
             sha256sum_file(str(expected_path)).hex(),
-            'd9506d541437f5e2892d6b6ea173f55233de11601650c157a27d8f2b9d08cb6f')
+            'e8c59b1bc1f19061c67eb7a392f4ea17eea83af58646ea2909e270546699c36c')
 
         assert_equal(
-            out['txoutset_hash'], 'd4453995f4f20db7bb3a604afd10d7128e8ee11159cde56d5b2fd7f55be7c74c')
+            out['txoutset_hash'], '771d773b5c27b6f35f598ce764652a2cf28fbc268341eb1827844e416c629c7d')
         assert_equal(out['nchaintx'], 101)
 
         # Specifying a path to an existing or invalid file will fail.
diff --git a/test/functional/rpc_getblockfrompeer.py b/test/functional/rpc_getblockfrompeer.py
index 841cde02197..9adcd88c9ee 100755
--- a/test/functional/rpc_getblockfrompeer.py
+++ b/test/functional/rpc_getblockfrompeer.py
@@ -128,7 +128,7 @@ class GetBlockFromPeerTest(BitcoinTestFramework):
         self.generate(self.nodes[0], 400, sync_fun=self.no_op)
         self.sync_blocks([self.nodes[0], pruned_node])
         pruneheight = pruned_node.pruneblockchain(300)
-        assert_equal(pruneheight, 248)
+        assert_equal(pruneheight, 249)
         # Ensure the block is actually pruned
         pruned_block = self.nodes[0].getblockhash(2)
         assert_raises_rpc_error(-1, "Block not available (pruned data)", pruned_node.getblock, pruned_block)
@@ -144,14 +144,14 @@ class GetBlockFromPeerTest(BitcoinTestFramework):
         self.log.info("Fetched block persists after next pruning event")
         self.generate(self.nodes[0], 250, sync_fun=self.no_op)
         self.sync_blocks([self.nodes[0], pruned_node])
-        pruneheight += 251
+        pruneheight += 252
         assert_equal(pruned_node.pruneblockchain(700), pruneheight)
         assert_equal(pruned_node.getblock(pruned_block)["hash"], "196ee3a1a6db2353965081c48ef8e6b031cb2115d084bec6fec937e91a2c6277")
 
         self.log.info("Fetched block can be pruned again when prune height exceeds the height of the tip at the time when the block was fetched")
         self.generate(self.nodes[0], 250, sync_fun=self.no_op)
         self.sync_blocks([self.nodes[0], pruned_node])
-        pruneheight += 250
+        pruneheight += 251
         assert_equal(pruned_node.pruneblockchain(1000), pruneheight)
         assert_raises_rpc_error(-1, "Block not available (pruned data)", pruned_node.getblock, pruned_block)
 
diff --git a/test/functional/test_framework/blocktools.py b/test/functional/test_framework/blocktools.py
index 0a393d89024..529f07cd3c7 100644
--- a/test/functional/test_framework/blocktools.py
+++ b/test/functional/test_framework/blocktools.py
@@ -161,11 +161,13 @@ def add_witness_commitment(block, nonce=0):
     block.hashMerkleRoot = block.calc_merkle_root()
 
 
-def script_BIP34_coinbase_height(height):
+def script_BIP34_coinbase_height(height, *, padding=True):
     if height <= 16:
         res = CScriptOp.encode_op_n(height)
-        # Append dummy extraNonce to increase scriptSig size to 2 (see bad-cb-length consensus rule)
-        return CScript([res, OP_0])
+        if padding:
+            # Append dummy extraNonce to increase scriptSig size to 2 (see bad-cb-length consensus rule)
+            return CScript([res, OP_0])
+        return CScript([res])
     return CScript([CScriptNum(height)])
 
 
diff --git a/test/functional/test_framework/ipc_util.py b/test/functional/test_framework/ipc_util.py
index 0e10b90e023..340cd15c618 100644
--- a/test/functional/test_framework/ipc_util.py
+++ b/test/functional/test_framework/ipc_util.py
@@ -109,9 +109,9 @@ async def make_capnp_init_ctx(self):
     return ctx, init
 
 
-async def mining_create_block_template(mining, stack, ctx, opts):
+async def mining_create_block_template(mining, stack, ctx, *args, **kwargs):
     """Call mining.createNewBlock() and return template, then call template.destroy() when stack exits."""
-    response = await mining.createNewBlock(ctx, opts)
+    response = await mining.createNewBlock(ctx, *args, **kwargs)
     if not response._has("result"):
         return None
     return await stack.enter_async_context(destroying(response.result, ctx))
diff --git a/test/functional/tool_bitcoin_chainstate.py b/test/functional/tool_bitcoin_chainstate.py
index c57da1fc376..6b7128898d2 100755
--- a/test/functional/tool_bitcoin_chainstate.py
+++ b/test/functional/tool_bitcoin_chainstate.py
@@ -20,7 +20,7 @@ from test_framework.wallet import MiniWallet
 START_HEIGHT = 199
 # Hardcoded in regtest chainparams
 SNAPSHOT_BASE_BLOCK_HEIGHT = 299
-SNAPSHOT_BASE_BLOCK_HASH = "7cc695046fec709f8c9394b6f928f81e81fd3ac20977bb68760fa1faa7916ea2"
+SNAPSHOT_BASE_BLOCK_HASH = "0c552ced4721c249a389eb9b08cb8da261cd46f0e7b5f9d064d48f3113406853"
 
 
 class BitcoinChainstateTest(BitcoinTestFramework):
diff --git a/test/functional/wallet_assumeutxo.py b/test/functional/wallet_assumeutxo.py
index a8c97be778f..3f28e36c805 100755
--- a/test/functional/wallet_assumeutxo.py
+++ b/test/functional/wallet_assumeutxo.py
@@ -172,7 +172,7 @@ class AssumeutxoTest(BitcoinTestFramework):
 
         assert_equal(
             dump_output['txoutset_hash'],
-            "d2b051ff5e8eef46520350776f4100dd710a63447a8e01d917e92e79751a63e2")
+            "106b2c56233e378a824cf0d5ff2be42ed32c72f1605c9be288d00942908a40ac")
         assert_equal(dump_output["nchaintx"], 334)
         assert_equal(n0.getblockchaininfo()["blocks"], SNAPSHOT_BASE_HEIGHT)