diff --git a/kittens/transfer/algorithm.c b/kittens/transfer/algorithm.c
index e51ffdb33..b584c1071 100644
--- a/kittens/transfer/algorithm.c
+++ b/kittens/transfer/algorithm.c
@@ -300,6 +300,7 @@ unserialize_op(uint8_t *data, size_t len, Operation *op) {
             consumed += op->data.len;
             break;
     }
+    if (consumed) op->type = data[0];
     return consumed;
 }
 
diff --git a/kitty_tests/file_transmission.py b/kitty_tests/file_transmission.py
index 459bc5f49..47ce9b888 100644
--- a/kitty_tests/file_transmission.py
+++ b/kitty_tests/file_transmission.py
@@ -123,7 +123,7 @@ def run_roundtrip_test(self: 'TestFileTransmission', src_data, changed, num_of_p
         p.apply_delta_data(delta[:11], read_at, write_changes)
         delta = delta[11:]
     p.finish_delta_data()
-    self.assertEqual(src_data, bytes(output))
+    self.assertEqual(src_data, bytes(output), f'\n\nsrc:\n{src_data.decode()}\nchanged:\n{changed.decode()}\noutput:\n{output.decode()}')
     limit = 2 * (p.block_size * num_of_patches)
     if limit > -1:
         self.assertLess(