bug#61703: 29.0.60; Emacs crashes on C-x 8 RET

[Gregory Heytings]

> > Indeed the choice of the default font seems relevant. The observed 
> > results:
> >
> > | Menlo (default monospace font) | crash    |
> > | Courier New                    | crash    |
> > | Courier Prime                  | no crash |
> > | JetBrains Mono                 | no crash |
> > | Cascadia Mono                  | crash    |
> > | Fira Code                      | no crash |
> > | Fira Mono                      | crash    |
>
> I'm on MS-Windows, where Courier New is the default font, and it still 
> doesn't crash...

FWIW, I tried that recipe here (Debian GNU/Linux) with Fira Mono, Menlo 
and Cascadia Mono, without experiencing any crash.  Perhaps it's a macOS 
specific bug.