Juri Linkov <juri@jurta.org> writes:
> Thanks for your patch.  Generally it works correctly, with few exceptions:
>
> 1. The function `buffer-list' returns a list of buried buffers in reverse
> order.  In the frame parameter `buried_buffer_list' the most recently
> buried buffer is first, so `buffer-list' misses a Fnreverse on `prevlist'.

Fixed.

> 2. Since `last-buffer' is a general function, I suggest to move it to
> simple.el.

Done.

> 3. Could you create a separate function from lambda which is now let-bound
> in `last-buffer'?  It could be named, for example, as `get-next-valid-buffer'.

Done.  New patch attached below.