bpo-43655: Tkinter and IDLE dialog windows are now recognized as dialogs by window managers on macOS and X Window (#25187)

diff --git a/Lib/idlelib/searchbase.py b/Lib/idlelib/searchbase.py
index fbef87a..64ed50c 100644
--- a/Lib/idlelib/searchbase.py
+++ b/Lib/idlelib/searchbase.py
@@ -2,6 +2,7 @@
 
 from tkinter import Toplevel
 from tkinter.ttk import Frame, Entry, Label, Button, Checkbutton, Radiobutton
+from tkinter.simpledialog import _setup_dialog
 
 
 class SearchDialogBase:
@@ -83,6 +84,7 @@ def create_widgets(self):
         top.protocol("WM_DELETE_WINDOW", self.close)
         top.wm_title(self.title)
         top.wm_iconname(self.icon)
+        _setup_dialog(top)
         self.top = top
         self.frame = Frame(top, padding="5px")
         self.frame.grid(sticky="nwes")