bug#48249: 28.0.50; Regression: emacs confused about window configuration due to ido-mode and/or winner-mode

[Gregory Heytings]

> > I wonder how many more bug reports are needed before the lesson of that 
> > failed experiment will finally be drawn.
>
> Significant changes in low-level infrastructure frequently cause a trail 
> of unintended consequences that need to be fixed.

When a low-level infrastructure has worked flawlessly for more than a 
decade, making significant changes in it without making them conditional 
to a run-time variable or a compilation option, until the new code is 
"proven" enough, is unwise.  That's what happened with native compilation 
for example, or with Cairo, or...  And this is all I asked when this 
experiment started.

> If you think what we saw till now as result of that changeset is a 
> catastrophe, you just didn't see enough serious low-level changes in 
> Emacs yet.

Did other low-level changes in Emacs result in segfaults and several bug 
reports of confused users each week?  I'd hope not.