diff --git a/electrum/transaction.py b/electrum/transaction.py
index 5bbbdf8ea..4d289951a 100644
--- a/electrum/transaction.py
+++ b/electrum/transaction.py
@@ -1483,11 +1483,15 @@ def convert_raw_tx_to_hex(raw: Union[str, bytes]) -> str:
     if not raw:
         raise ValueError("empty string")
     raw_unstripped = raw
-    # remove all whitespace characters
-    if isinstance(raw, str):
+    # try to remove whitespaces.
+    # FIXME we should NOT do *any* whitespace mangling for bytes-like inputs, only str
+    raw = raw.strip()  # remove leading/trailing whitespace, even if bytes-like
+    if isinstance(raw, str):  # remove all whitespace characters, if str
+        # note: we don't do this for bytes-like inputs, as whitespace-looking bytes can appear
+        #       anywhere in a raw tx. Even leading/trailing pseudo-whitespace: consider that
+        #       the nVersion or the nLocktime might contain "0a" bytes
+        #       consider e.g.:  "\n".encode().hex() == "0a"
         raw = re.sub(r'\s', '', raw)
-    else:
-        raw = re.sub(rb'\s', b'', raw)
     # try hex
     try:
         return binascii.unhexlify(raw).hex()
@@ -1529,7 +1533,7 @@ def tx_from_any(raw: Union[str, bytes], *,
         return tx
     except Exception as e:
         raise SerializationError(f"Failed to recognise tx encoding, or to parse transaction. "
-                                 f"raw: {raw[:30]}...") from e
+                                 f"raw: {raw[:30]!r}...") from e
 
 
 class PSBTGlobalType(IntEnum):
diff --git a/tests/test_transaction.py b/tests/test_transaction.py
index ed74461e8..6d10fb6b4 100644
--- a/tests/test_transaction.py
+++ b/tests/test_transaction.py
@@ -276,11 +276,11 @@ class TestTransaction(ElectrumTestCase):
                         data = raw_tx.data
                         tx_from_any(data)  # test if raises (should not)
                     else:
-                        mid = len(raw_tx.data) // 2
                         if isinstance(raw_tx.data, str):
+                            mid = len(raw_tx.data) // 2  # for str, sprinkle whitespaces all over
                             data = whitespace_str + raw_tx.data[:mid] + whitespace_str + raw_tx.data[mid:] + whitespace_str
-                        else:
-                            data = whitespace_bytes + raw_tx.data[:mid] + whitespace_bytes + raw_tx.data[mid:] + whitespace_bytes
+                        else:  # bytes only tolerate whitespaces that are leading/trailing
+                            data = whitespace_bytes + raw_tx.data + whitespace_bytes
                         if raw_tx.is_whitespace_allowed:
                             tx_from_any(data)  # test if raises (should not)
                         else: