bug#64497: 30.0.50; `other-buffer' returns current buffer

[Eli Zaretskii]

> Date: Thu, 06 Jul 2023 17:16:21 +0100
> From: hugo@heagren.com
> 
> I've just built Emacs from master. My binding to
> `mode-line-other-buffer' wasn't doing what it should, so I investigated.
> On my machine, the form `(other-buffer)' returns the current buffer.
> 
> I notice that a recent change to `other-buffer' relates to scratch
> buffers (though my C isn't good enough to know what it really does). I
> have tested this in a scratch buffer, and there too `(other-buffer)'
> returns the current buffer (i.e. *scratch*).
> 
> `(other-buffer (current-buffer))' behaves as it -- i.e. returns a buffer
> other than the current buffer.

I cannot reproduce this with the current master branch, FWIW.