This feature may be fine or it may not.  I haven't been able to apply the PR and get a working Python 3.9 with Tkinter support, nor have I seen the requested additional screen shots.

Ideally, major changes in appearance or functionality should have significant user testing and feedback.  However, the tone of this thread is that the user feedback is irrelevant and the feature will happen and be backported regardless.

My team has used IDLE 8 hours a day for the last eight years, cumulatively training 25,000+ engineers using IDLE.  We have served as the beta tester and as the canary in the coal mine, reporting every usability issue so that IDLE can be improved.  We have tried to be a voice for users and it is sad to be roundly dismissed.

Other bug reports and feature requests that matter to us don't appear to be getting any traction:

* The squeezer on-by-default degraded our user experience
* Need auto-save shell sessions (we record full day sessions)
* Print speed is slow, giving the appearance of Python being slow
* Need Alt +/- hot keys for changing font size
* Recently lost the strip-trailing-whitespace menu option
* Need auto-strip-trailing-whitespace on save
* Tab completion has been unreliable for several years
* Need an option to run the install-certificates script (otherwise urllib HTTP requests fail with a fresh install of Python from python.org)
* Cntl-A on macOS jumps before the >>> prompt
* Font samples on the Settings tab are useless, distracting, and so large that it can make it impossible to mouse down to the Ok or Apply buttons when the display size is small (constrained by the projector).
* The tab size slider should be a scroll box and the font size scroll-box should be slider (users should almost never change the tab size but almost always want to change the font size).
* The default font size is too small.  For some users, when IDLE opens, the text looks like dust.
* The completions pop-up menu has never been helpful and users have a hard time getting it dismissed (so we usually have people change the completions pop-up time to 10,000 milliseconds)
* The mouse cursor targeting frequently gets missed by about seven lines (my understanding is that this is an upstream Tkinter problem, but it has been around for many years -- we have to close and reopen windows frequently to make this goa away).
* For the past two or three years, we periodically get an unintentional clipboard paste in to the shell window.  This happens during live demos, so the instructors have been accustomed to reflexively type Cntl-Z to undo the paste so as not to interrupt the demo).
* For mac users who have enabled tabs system-wide, opening a new window in IDLE triggers a system log-out (amazing that this is even possible).  My understanding is there isn't anything we can do about this, but it is a really bad out-of-the-box user experience seconds after a fresh install of Python.
* On rare occasion, I teach Python to kids.  A menu option to launch the turtle demo would be helpful.
* Being able to run pip from within IDLE would be a major win, especially for Windows users who are foreign to the command-line and who often do have Python on the PATH.
* The Search Dialog window doesn't stay on top of other windows.  It can have the focus, but be hidden underneath other windows.  The user experience that is there is no key that they can press to continue running their session.
* Sometimes the Search Dialog window becomes unresponsive and there is no way to clear it without turning IDLE off.
* When launching IDLE from the command-line, we see various exceptions and tracebacks for errors in the code (typically along the lines of None-type object doesn't have some attribute).
* Several of these issues have only came-up in the past few years.  IDLE used to be more stable than it is now.