bug#68958: [PATCH] Support bookmarking Xref results buffers

[Juri Linkov]

> This patch adds support for bookmarking "*xref*" buffers and restoring
> them later, even across Emacs sessions.

Shouldn't 'revert-buffer-function' in the xref buffer
be sufficient to reconstruct the buffer contents?

Usually modes set buffer-local 'revert-buffer-function'
to a lambda that reruns the top function with previous
arguments.  But it seems xref.el doesn't set it.

I once tried to use 'revert-buffer-function' to restore
xref buffers from the desktop, but abandoned the idea.
Not because xref.el doesn't set 'revert-buffer-function'.
But because it would take too much time to restore
the desktop while it will rerun all saved xref buffers.

OTOH, saving an xref bookmark makes more sense.
And probably your patch will help to implement
'revert-buffer-function' for xref as well.