If we use a buffer local, I'll have to remove it after make-frame is complete. If a let-bound variable, users would not have to remember to do this. Either way, make_frame needs to ignore the specified buffer that happens to be hidden.

On Sat, Jan 25, 2025 at 2:17 PM martin rudalics <rudalics@gmx.at> wrote:

> I'd be happy with a new defvar (not even a defcustom) and I'll bind it all
> the time (except in packages where I'll bind it around make-frame calls).

I think a new automatically buffer-local variable, say
'display-via-make-frame', would not harm anyone.

martin