Thanks for the quick response, Marc. The results of testing were mixed. The good news: the new version did seem to solve the Monterey problem of the "UFO" and the loss of keyboard focus. However, the new version causes new problems on other releases.

- On 10.14 and earlier systems, I observed the following new behavior in IDLE: on doing a Save from an Edit Window (either with CMD-S or click on the Save menu item), the Save file pane appears as expected but, after entering the file name and clicking Save on the pane, the Save file pane is not dismissed although the file is actually saved under the expected file name. Clicking on the pane's Save button again brings up a "file already exists, do you want to overwrite" message and after clicking OK to that, both the "overwrite" pane and the underlying Save pane are dismissed.

- On 10.15 only, I stumbled across this behavior (and verified it did not occur with the unpatched 8.6.11 nor does it seem to occur anywhere but on 10.15): in a new IDLE edit window, type some text, then Save to a file (CMD-S). Now alter the text and then use Save As (CMD-SHIFT-S) to attempt to save to another file name. Upon entering CMD-SHIFT-S (or clicking on the Save As... menu item), Tk crashes. I've attached a few crash dumps.