diff --git a/Lib/idlelib/editor.py b/Lib/idlelib/editor.py
index 08d6aa2efde22a..543882a4b568a8 100644
--- a/Lib/idlelib/editor.py
+++ b/Lib/idlelib/editor.py
@@ -1624,6 +1624,8 @@ def prepstr(s):
  'bracketleft': '[',
  'bracketright': ']',
  'slash': '/',
+ 'backslash': '\\',
+ 'space': 'Space' if macosx.isCocoaTk() else 'space',  # GH-88564.
 }
 
 def get_accelerator(keydefs, eventname):