diff --git a/electrum/bitcoin.py b/electrum/bitcoin.py
index b2959f021..43afc6bbb 100644
--- a/electrum/bitcoin.py
+++ b/electrum/bitcoin.py
@@ -23,19 +23,17 @@
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 import binascii
-import hashlib
 from typing import List, Tuple, TYPE_CHECKING, Optional, Union, NamedTuple
 from eth_abi import encode_abi, decode_abi
 from eth_utils import function_abi_to_4byte_selector
 import enum
 from enum import IntEnum, Enum
 
-from .util import bfh, bh2u, BitcoinException, assert_bytes, to_bytes, inv_dict
-from . import version
+from .util import bfh, BitcoinException, assert_bytes, to_bytes, inv_dict
 from . import segwit_addr
 from . import constants
 from . import ecc
-from .crypto import sha256d, sha256, hash_160, hmac_oneshot
+from .crypto import sha256d, sha256, hash_160
 
 if TYPE_CHECKING:
     from .network import Network
@@ -459,7 +457,7 @@ def address_to_script(addr: str, *, net=None) -> str:
         script = pubkeyhash_to_p2pkh_script(hash_160_.hex())
     elif addrtype == net.ADDRTYPE_P2SH:
         script = opcodes.OP_HASH160.hex()
-        script += push_script(bh2u(hash_160_))
+        script += push_script(hash_160_.hex())
         script += opcodes.OP_EQUAL.hex()
     else:
         raise BitcoinException(f'unknown address type: {addrtype}')
@@ -506,7 +504,7 @@ def address_to_scripthash(addr: str) -> str:
 
 def script_to_scripthash(script: str) -> str:
     h = sha256(bfh(script))[0:32]
-    return bh2u(bytes(reversed(h)))
+    return bytes(reversed(h)).hex()
 
 
 def public_key_to_p2pk_script(pubkey: str) -> str:
@@ -612,7 +610,7 @@ def DecodeBase58Check(psz: Union[bytes, str]) -> bytes:
     csum_found = vchRet[-4:]
     csum_calculated = sha256d(payload)[0:4]
     if csum_calculated != csum_found:
-        raise InvalidChecksum(f'calculated {bh2u(csum_calculated)}, found {bh2u(csum_found)}')
+        raise InvalidChecksum(f'calculated {csum_calculated.hex()}, found {csum_found.hex()}')
     else:
         return payload
 
diff --git a/electrum/blockchain.py b/electrum/blockchain.py
index d277aaf81..248172a1f 100644
--- a/electrum/blockchain.py
+++ b/electrum/blockchain.py
@@ -31,7 +31,7 @@
 from .bitcoin import hash_encode, int_to_hex, rev_hex, var_int
 from .crypto import sha256d
 from . import constants
-from .util import bfh, bh2u, unpack_uint16_from, unpack_int32_from, unpack_uint32_from, unpack_int64_from, unpack_uint64_from
+from .util import bfh, unpack_uint16_from, unpack_int32_from, unpack_uint32_from, unpack_int64_from, unpack_uint64_from
 from .simple_config import SimpleConfig
 from .logging import get_logger, Logger
 
diff --git a/electrum/constants.py b/electrum/constants.py
index 845c0a97a..8a06e8af0 100644
--- a/electrum/constants.py
+++ b/electrum/constants.py
@@ -142,7 +142,7 @@ class QtumTestnet(AbstractNet):
     QIP5_FORK_HEIGHT = 446320
     QIP9_FORK_HEIGHT = 446320
     OFFLINE_STAKE_HEIGHT = 625000
-    USE_OPSENDER = False
+    USE_OPSENDER = True
 
     LN_REALM_BYTE = 0
     LN_DNS_SEEDS = []
diff --git a/electrum/gui/qt/main_window.py b/electrum/gui/qt/main_window.py
index 25d874fc4..e1ed45169 100644
--- a/electrum/gui/qt/main_window.py
+++ b/electrum/gui/qt/main_window.py
@@ -3359,12 +3359,10 @@ def call_add_delegation(self, addr, staker, fee, gas_limit, gas_price, dialog):
         """
         :param staker: hash160 str
         """
+        password = None
         if self.wallet.has_keystore_encryption():
             password = self.password_dialog(_("Enter your password to proceed"))
-            if not password:
-                return
-        else:
-            password = None
+            if not password: return
 
         pod = self.wallet.sign_message(addr, staker, password)
         args = [staker.lower(), fee, pod]
@@ -3372,12 +3370,11 @@ def call_add_delegation(self, addr, staker, fee, gas_limit, gas_price, dialog):
                                    gas_limit, gas_price, 0, addr, dialog, False, password, tx_desc="update delegation")
 
     def call_remove_delegation(self, addr, gas_limit, gas_price, dialog):
+        password = None
         if self.wallet.has_keystore_encryption():
             password = self.password_dialog(_("Enter your password to proceed"))
-            if not password:
-                return
-        else:
-            password = None
+            if not password: return
+
         self.sendto_smart_contract(DELEGATION_CONTRACT, DELEGATE_ABI[0], [],
                                    gas_limit, gas_price, 0, addr, dialog, False, password, tx_desc="remove delegation")
 
diff --git a/electrum/mnemonic.py b/electrum/mnemonic.py
index 6e0f0e687..fd7e20642 100644
--- a/electrum/mnemonic.py
+++ b/electrum/mnemonic.py
@@ -30,7 +30,7 @@
 from typing import Sequence, Dict
 from types import MappingProxyType
 
-from .util import resource_path, bfh, bh2u, randrange
+from .util import resource_path, bfh, randrange
 from .crypto import hmac_oneshot
 from . import version
 from .logging import Logger
@@ -217,7 +217,7 @@ def make_seed(self, seed_type=None, *, num_bits=132) -> str:
 
 def is_new_seed(x: str, prefix=version.SEED_PREFIX) -> bool:
     x = normalize_text(x)
-    s = bh2u(hmac_oneshot(b"Seed version", x.encode('utf8'), hashlib.sha512))
+    s = hmac_oneshot(b"Seed version", x.encode('utf8'), hashlib.sha512).hex()
     return s.startswith(prefix)
 
 
diff --git a/electrum/network.py b/electrum/network.py
index 582deed12..c861f640d 100644
--- a/electrum/network.py
+++ b/electrum/network.py
@@ -43,14 +43,13 @@
 
 from . import util
 from .util import (log_exceptions, ignore_exceptions,
-                   bfh, SilentTaskGroup, make_aiohttp_session, send_exception_to_crash_reporter,
-                   is_hash256_str, is_non_negative_integer, bh2u, MyEncoder, NetworkRetryManager)
+                   SilentTaskGroup, make_aiohttp_session, send_exception_to_crash_reporter,
+                   MyEncoder, NetworkRetryManager)
 
 from .bitcoin import COIN, b58_address_to_hash160, TOKEN_TRANSFER_TOPIC, DELEGATION_CONTRACT, DELEGATE_ABI, eth_output_decode
 from . import constants
 from . import blockchain
 from . import bitcoin
-from .blockchain import Blockchain
 from . import dns_hacks
 from .transaction import Transaction
 from .blockchain import Blockchain
@@ -1337,18 +1336,18 @@ async def call_contract(self, address, data, sender):
 
     async def request_token_balance(self, bind_addr, contract_addr):
         __, hash160 = b58_address_to_hash160(bind_addr)
-        hash160 = bh2u(hash160)
+        hash160 = hash160.hex()
         datahex = '70a08231{}'.format(hash160.zfill(64))
         return await self.interface.session.send_request('blockchain.contract.call', [contract_addr, datahex, '', 'int'])
 
     async def request_token_history(self, bind_addr, contract_addr):
         __, hash160 = b58_address_to_hash160(bind_addr)
-        hash160 = bh2u(hash160)
+        hash160 = hash160.hex()
         return await self.interface.session.send_request('blockchain.contract.event.get_history', [hash160, contract_addr, TOKEN_TRANSFER_TOPIC])
 
     async def request_delegation_info(self, addr):
         __, hash160 = b58_address_to_hash160(addr)
-        hash160 = bh2u(hash160)
+        hash160 = hash160.hex()
         datahex = 'bffe3486{}'.format(hash160.zfill(64))
         result = await self.call_contract(DELEGATION_CONTRACT, datahex, '')
         return eth_output_decode(DELEGATE_ABI[2], result)
diff --git a/electrum/util.py b/electrum/util.py
index 45297c652..1bc9fe8cc 100644
--- a/electrum/util.py
+++ b/electrum/util.py
@@ -917,7 +917,7 @@ def parse_URI(uri: str, on_pr: Callable = None, *, loop=None) -> dict:
             raise InvalidBitcoinURI(f"failed to parse 'exp' field: {repr(e)}") from e
     if 'sig' in out:
         try:
-            out['sig'] = bh2u(bitcoin.base_decode(out['sig'], base=58))
+            out['sig'] = bitcoin.base_decode(out['sig'], base=58).hex()
         except Exception as e:
             raise InvalidBitcoinURI(f"failed to parse 'sig' field: {repr(e)}") from e