diff --git a/Lib/idlelib/AutoCompleteWindow.py b/Lib/idlelib/AutoCompleteWindow.py
index f666ea628bb..2ee6878396d 100644
--- a/Lib/idlelib/AutoCompleteWindow.py
+++ b/Lib/idlelib/AutoCompleteWindow.py
@@ -192,6 +192,7 @@ def show_window(self, comp_lists, index, complete, mode, userWantsWin):
         scrollbar.config(command=listbox.yview)
         scrollbar.pack(side=RIGHT, fill=Y)
         listbox.pack(side=LEFT, fill=BOTH, expand=True)
+        acw.lift()  # work around bug in Tk 8.5.18+ (issue #24570)
 
         # Initialize the listbox selection
         self.listbox.select_set(self._binary_search(self.start))
diff --git a/Lib/idlelib/CallTipWindow.py b/Lib/idlelib/CallTipWindow.py
index 170d14653a2..8e68a76b2a8 100644
--- a/Lib/idlelib/CallTipWindow.py
+++ b/Lib/idlelib/CallTipWindow.py
@@ -72,6 +72,7 @@ def showtip(self, text, parenleft, parenright):
                            background="#ffffe0", relief=SOLID, borderwidth=1,
                            font = self.widget['font'])
         self.label.pack()
+        tw.lift()  # work around bug in Tk 8.5.18+ (issue #24570)
 
         self.checkhideid = self.widget.bind(CHECKHIDE_VIRTUAL_EVENT_NAME,
                                             self.checkhide_event)