bug#53284: 28.0.91; TRAMP SSHFS: process-file with remote input file doesn't work

[Philipp Stephani]

Am Mo., 17. Jan. 2022 um 10:53 Uhr schrieb Michael Albinus
<michael.albinus@gmx.de>:
>
> Version: 29.1
>
> Philipp Stephani <p.stephani2@gmail.com> writes:
>
> Hi Philipp,
>
> >> Could you pls try the appended patch?
> >
> > That appears to fix it for me, thanks.
>
> Thanks for feedback. During my regression tests I've found some further
> oddities in this area, so I have pushed an extended patch to
> master. This will also be available with the next GNU ELPA Tramp
> release, 2.5.2.1, end of this month. Closing the bug.

Thanks. Any objections to backporting the fixes to the release branch?
The bug is rather annoying, and the fixes can't break anything (since
SSHFS wasn't supported in Emacs 27).