diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 1cc7d718c..c6a3c6180 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -3755,7 +3755,7 @@ void Blockchain::set_enforce_dns_checkpoints(bool enforce_checkpoints)
 }
 
 //------------------------------------------------------------------
-void Blockchain::block_longhash_worker(uint64_t height, const std::vector<block> &blocks, std::unordered_map<crypto::hash, crypto::hash> &map) const
+void Blockchain::block_longhash_worker(uint64_t height, const epee::span<const block> &blocks, std::unordered_map<crypto::hash, crypto::hash> &map) const
 {
   TIME_MEASURE_START(t);
   slow_hash_allocate_state();
@@ -3841,11 +3841,33 @@ bool Blockchain::cleanup_handle_incoming_blocks(bool force_sync)
 }
 
 //------------------------------------------------------------------
-void Blockchain::output_scan_worker(const uint64_t amount, const std::vector<uint64_t> &offsets, std::vector<output_data_t> &outputs) const
+void Blockchain::output_scan_worker(const uint64_t amount, const std::vector<uint64_t> &offsets, std::vector<output_data_t> &outputs, const std::vector<output_data_t> &extra_tx_map) const
 {
   try
   {
     m_db->get_output_key(epee::span<const uint64_t>(&amount, 1), offsets, outputs, true);
+    if (outputs.size() < offsets.size())
+    {
+      const uint64_t n_outputs = m_db->get_num_outputs(amount);
+      for (size_t i = outputs.size(); i < offsets.size(); ++i)
+      {
+        uint64_t idx = offsets[i];
+        if (idx < n_outputs)
+        {
+          MWARNING("Index " << idx << " not found in db for amount " << amount << ", but it is less than the number of entries");
+          break;
+        }
+        else if (idx < n_outputs + extra_tx_map.size())
+        {
+          outputs.push_back(extra_tx_map[idx - n_outputs]);
+        }
+        else
+        {
+          MWARNING("missed " << amount << "/" << idx << " in " << extra_tx_map.size() << " (chain " << n_outputs << ")");
+          break;
+        }
+      }
+    }
   }
   catch (const std::exception& e)
   {
@@ -3960,6 +3982,34 @@ uint64_t Blockchain::prevalidate_block_hashes(uint64_t height, const std::vector
 //    vs [k_image, output_keys] (m_scan_table). This is faster because it takes advantage of bulk queries
 //    and is threaded if possible. The table (m_scan_table) will be used later when querying output
 //    keys.
+static bool update_output_map(std::map<uint64_t, std::vector<output_data_t>> &extra_tx_map, const transaction &tx, uint64_t height, bool miner)
+{
+  MTRACE("Blockchain::" << __func__);
+  for (size_t i = 0; i < tx.vout.size(); ++i)
+  {
+    const auto &out = tx.vout[i];
+    if (out.target.type() != typeid(txout_to_key))
+      continue;
+    const txout_to_key &out_to_key = boost::get<txout_to_key>(out.target);
+    rct::key commitment;
+    uint64_t amount = out.amount;
+    if (miner && tx.version == 2)
+    {
+      commitment = rct::zeroCommit(amount);
+      amount = 0;
+    }
+    else if (tx.version > 1)
+    {
+      CHECK_AND_ASSERT_MES(i < tx.rct_signatures.outPk.size(), false, "Invalid outPk size");
+      commitment = tx.rct_signatures.outPk[i].mask;
+    }
+    else
+      commitment = rct::zero();
+    extra_tx_map[amount].push_back(output_data_t{out_to_key.key, tx.unlock_time, height, commitment});
+  }
+  return true;
+}
+
 bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete_entry> &blocks_entry)
 {
   MTRACE("Blockchain::" << __func__);
@@ -4006,42 +4056,40 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
     m_blockchain_lock.lock();
   }
 
-  if ((m_db->height() + blocks_entry.size()) < m_blocks_hash_check.size())
+  const uint64_t height = m_db->height();
+  if ((height + blocks_entry.size()) < m_blocks_hash_check.size())
     return true;
 
   bool blocks_exist = false;
   tools::threadpool& tpool = tools::threadpool::getInstance();
-  uint64_t threads = tpool.get_max_concurrency();
+  unsigned threads = tpool.get_max_concurrency();
+  std::vector<block> blocks;
+  blocks.resize(blocks_entry.size());
 
-  if (blocks_entry.size() > 1 && threads > 1 && m_max_prepare_blocks_threads > 1)
+  if (1)
   {
     // limit threads, default limit = 4
     if(threads > m_max_prepare_blocks_threads)
       threads = m_max_prepare_blocks_threads;
 
-    uint64_t height = m_db->height();
-    int batches = blocks_entry.size() / threads;
-    int extra = blocks_entry.size() % threads;
+    unsigned int batches = blocks_entry.size() / threads;
+    unsigned int extra = blocks_entry.size() % threads;
     MDEBUG("block_batches: " << batches);
     std::vector<std::unordered_map<crypto::hash, crypto::hash>> maps(threads);
-    std::vector < std::vector < block >> blocks(threads);
     auto it = blocks_entry.begin();
+    unsigned blockidx = 0;
 
-    for (uint64_t i = 0; i < threads; i++)
+    for (unsigned i = 0; i < threads; i++)
     {
-      blocks[i].reserve(batches + 1);
-      for (int j = 0; j < batches; j++)
+      for (unsigned int j = 0; j < batches; j++, ++blockidx)
       {
-        block block;
+        block &block = blocks[blockidx];
 
         if (!parse_and_validate_block_from_blob(it->block, block))
-        {
-          std::advance(it, 1);
-          continue;
-        }
+          return false;
 
         // check first block and skip all blocks if its not chained properly
-        if (i == 0 && j == 0)
+        if (blockidx == 0)
         {
           crypto::hash tophash = m_db->top_block_hash();
           if (block.prev_id != tophash)
@@ -4056,20 +4104,16 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
           break;
         }
 
-        blocks[i].push_back(std::move(block));
         std::advance(it, 1);
       }
     }
 
-    for (int i = 0; i < extra && !blocks_exist; i++)
+    for (unsigned i = 0; i < extra && !blocks_exist; i++, blockidx++)
     {
-      block block;
+      block &block = blocks[blockidx];
 
       if (!parse_and_validate_block_from_blob(it->block, block))
-      {
-        std::advance(it, 1);
-        continue;
-      }
+        return false;
 
       if (have_block(get_block_hash(block)))
       {
@@ -4077,7 +4121,6 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
         break;
       }
 
-      blocks[i].push_back(std::move(block));
       std::advance(it, 1);
     }
 
@@ -4086,10 +4129,13 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
       m_blocks_longhash_table.clear();
       uint64_t thread_height = height;
       tools::threadpool::waiter waiter;
-      for (uint64_t i = 0; i < threads; i++)
+      for (unsigned int i = 0; i < threads; i++)
       {
-        tpool.submit(&waiter, boost::bind(&Blockchain::block_longhash_worker, this, thread_height, std::cref(blocks[i]), std::ref(maps[i])), true);
-        thread_height += blocks[i].size();
+        unsigned nblocks = batches;
+        if (i < extra)
+          ++nblocks;
+        tpool.submit(&waiter, boost::bind(&Blockchain::block_longhash_worker, this, thread_height, epee::span<const block>(&blocks[i], nblocks), std::ref(maps[i])), true);
+        thread_height += nblocks;
       }
 
       waiter.wait(&tpool);
@@ -4132,7 +4178,7 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
   // [input] stores all absolute_offsets for each amount
   std::map<uint64_t, std::vector<uint64_t>> offset_map;
   // [output] stores all output_data_t for each absolute_offset
-  std::map<uint64_t, std::vector<output_data_t>> tx_map;
+  std::map<uint64_t, std::vector<output_data_t>> tx_map, extra_tx_map;
   std::vector<std::pair<cryptonote::transaction, crypto::hash>> txes(total_txs);
 
 #define SCAN_TABLE_QUIT(m) \
@@ -4143,12 +4189,14 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
         } while(0); \
 
   // generate sorted tables for all amounts and absolute offsets
-  size_t tx_index = 0;
+  size_t tx_index = 0, block_index = 0;
   for (const auto &entry : blocks_entry)
   {
     if (m_cancel)
       return false;
 
+    if (!update_output_map(extra_tx_map, blocks[block_index].miner_tx, height + block_index, true))
+      SCAN_TABLE_QUIT("Error building extra tx map.");
     for (const auto &tx_blob : entry.txs)
     {
       if (tx_index >= txes.size())
@@ -4207,7 +4255,10 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
           offset_map[in_to_key.amount].push_back(offset);
 
       }
+      if (!update_output_map(extra_tx_map, tx, height + block_index, false))
+        SCAN_TABLE_QUIT("Error building extra tx map.");
     }
+    ++block_index;
   }
 
   // sort and remove duplicate absolute_offsets in offset_map
@@ -4230,7 +4281,7 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
     for (size_t i = 0; i < amounts.size(); i++)
     {
       uint64_t amount = amounts[i];
-      tpool.submit(&waiter, boost::bind(&Blockchain::output_scan_worker, this, amount, std::cref(offset_map[amount]), std::ref(tx_map[amount])), true);
+      tpool.submit(&waiter, boost::bind(&Blockchain::output_scan_worker, this, amount, std::cref(offset_map[amount]), std::ref(tx_map[amount]), std::cref(extra_tx_map[amount])), true);
     }
     waiter.wait(&tpool);
   }
@@ -4239,7 +4290,7 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
     for (size_t i = 0; i < amounts.size(); i++)
     {
       uint64_t amount = amounts[i];
-      output_scan_worker(amount, offset_map[amount], tx_map[amount]);
+      output_scan_worker(amount, offset_map[amount], tx_map[amount], extra_tx_map[amount]);
     }
   }
 
diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h
index f1e366c9e..877828f81 100644
--- a/src/cryptonote_core/blockchain.h
+++ b/src/cryptonote_core/blockchain.h
@@ -918,7 +918,7 @@ namespace cryptonote
      * @param outputs return-by-reference the outputs collected
      */
     void output_scan_worker(const uint64_t amount,const std::vector<uint64_t> &offsets,
-        std::vector<output_data_t> &outputs) const;
+        std::vector<output_data_t> &outputs, const std::vector<output_data_t> &extra_tx_map) const;
 
     /**
      * @brief computes the "short" and "long" hashes for a set of blocks
@@ -927,7 +927,7 @@ namespace cryptonote
      * @param blocks the blocks to be hashed
      * @param map return-by-reference the hashes for each block
      */
-    void block_longhash_worker(uint64_t height, const std::vector<block> &blocks,
+    void block_longhash_worker(uint64_t height, const epee::span<const block> &blocks,
         std::unordered_map<crypto::hash, crypto::hash> &map) const;
 
     /**