diff --git a/Lib/idlelib/EditorWindow.py b/Lib/idlelib/EditorWindow.py
index 19bbdd60f9b..27c989cb117 100644
--- a/Lib/idlelib/EditorWindow.py
+++ b/Lib/idlelib/EditorWindow.py
@@ -316,9 +316,6 @@ class EditorWindow(object):
                     self.good_load = True
                     is_py_src = self.ispythonsource(filename)
                     self.set_indentation_params(is_py_src)
-                    if is_py_src:
-                        self.color = color = self.ColorDelegator()
-                        per.insertfilter(color)
             else:
                 io.set_filename(filename)
                 self.good_load = True
diff --git a/Lib/idlelib/PyShell.py b/Lib/idlelib/PyShell.py
index 177e49e55e4..1805644b6ec 100644
--- a/Lib/idlelib/PyShell.py
+++ b/Lib/idlelib/PyShell.py
@@ -858,8 +858,6 @@ class PyShell(OutputWindow):
         text.bind("<<open-stack-viewer>>", self.open_stack_viewer)
         text.bind("<<toggle-debugger>>", self.toggle_debugger)
         text.bind("<<toggle-jit-stack-viewer>>", self.toggle_jit_stack_viewer)
-        self.color = color = self.ColorDelegator()
-        self.per.insertfilter(color)
         if use_subprocess:
             text.bind("<<view-restart>>", self.view_restart_mark)
             text.bind("<<restart-shell>>", self.restart_shell)
diff --git a/Misc/NEWS b/Misc/NEWS
index b4ba70ba78a..39e580b20e6 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -135,6 +135,8 @@ Library
 IDLE
 ----
 
+- Issue #13495: Avoid loading the color delegator twice in IDLE.
+
 - Issue #17798: Allow IDLE to edit new files when specified on command line.
 
 - Issue #14735: Update IDLE docs to omit "Control-z on Windows".