Marc, thanks for providing the patch for Tk. There are some issues with it, though, at least when used with IDLE. I built a Python 3.10.0+ universal2 installer, like what we provide on python.org, with just the updated Tk and tested it on macOS 10.9, 10.13, 10.14, 10.15, 11 and 12.

First, and most important, there seems to be a typo in the fix that causes the dialog panel to break on macOS 10.14: 

-	if ([NSApp macOSVersion] > 101400) {
+	if ( osVersion >= 101400 && osVersion < 120000) {

That ">=" should be just an ">" as before, I think. At least, making that change unbreaks 10.14.

Second, while the filedialog panel now works on macOS 12 (Monterey) with the patch, there are some side effects, at least when using CMD-S (Save) in a new IDLE edit window. After pressing CMD-S, some small object appears on the screen very briefly (too quickly for me to recognize what it is) and then the expected Save filedialog panel appears; however, unlike on all the other operating system levels tested, the keyboard focus is not on the filename text field in the panel. So when the user starts typing the file name, nothing happens until they do something, like clicking on the file name field, to manually move the keyboard focus to that field. I think most users would find that confusing. I don't know if there's any way to change that, either in Tk, tkinter, or IDLE. But it does seem to be a regression. The same binaries work fine on all of the other macOS versions I tested.

Any ideas?

(Although it's not an IDLE bug, I've added IDLE to the components list since it is impacted by this issue.)