diff --git a/src/textual/_xterm_parser.py b/src/textual/_xterm_parser.py
index 7a90a16bb..042861e63 100644
--- a/src/textual/_xterm_parser.py
+++ b/src/textual/_xterm_parser.py
@@ -2,7 +2,6 @@ from __future__ import annotations
 
 
 import re
-from collections import deque
 from typing import Any, Callable, Generator, Iterable
 
 from . import messages
@@ -36,11 +35,11 @@ class XTermParser(Parser[events.Event]):
         self.last_x = 0
         self.last_y = 0
 
-        self._debug_log_file = open("keys.log", "wt")
+        self._debug_log_file = open("keys.log", "wt") if debug else None
 
         super().__init__()
 
-    def debug_log(self, *args: Any) -> None:
+    def debug_log(self, *args: Any) -> None:  # pragma: no cover
         if self._debug_log_file is not None:
             self._debug_log_file.write(" ".join(args) + "\n")
             self._debug_log_file.flush()
@@ -187,12 +186,13 @@ class XTermParser(Parser[events.Event]):
                         mouse_match = _re_mouse_event.match(sequence)
                         if mouse_match is not None:
                             mouse_code = mouse_match.group(0)
-                            print(mouse_code)
                             event = self.parse_mouse_code(mouse_code, self.sender)
                             if event:
                                 on_token(event)
                             break
-                        # Or a mode report? (i.e. the terminal telling us if it supports a mode we requested)
+
+                        # Or a mode report?
+                        # (i.e. the terminal saying it supports a mode we requested)
                         mode_report_match = _re_terminal_mode_response.match(sequence)
                         if mode_report_match is not None:
                             if (
diff --git a/tests/test_xterm_parser.py b/tests/test_xterm_parser.py
index 84b60d505..c1937ffc0 100644
--- a/tests/test_xterm_parser.py
+++ b/tests/test_xterm_parser.py
@@ -3,8 +3,15 @@ from unittest import mock
 import pytest
 
 from textual._xterm_parser import XTermParser
-from textual.events import Paste, Key, MouseDown, MouseUp, MouseMove, MouseScrollDown, \
-    MouseScrollUp
+from textual.events import (
+    Paste,
+    Key,
+    MouseDown,
+    MouseUp,
+    MouseMove,
+    MouseScrollDown,
+    MouseScrollUp,
+)
 from textual.messages import TerminalSupportsSynchronizedOutput
 
 
@@ -207,6 +214,13 @@ def test_mouse_scroll_up(parser, sequence, shift, meta):
     assert event.y == 24
 
 
+def test_mouse_event_detected_but_info_not_parsed(parser):
+    # I don't know if this can actually happen in reality, but
+    # there's a branch in the code that allows for the possibility.
+    events = list(parser.feed("\x1b[<65;18;20;25M"))
+    assert len(events) == 0
+
+
 def test_escape_sequence_resulting_in_multiple_keypresses(parser):
     """Some sequences are interpreted as more than 1 keypress"""
     events = list(parser.feed("\x1b[2;4~"))