bug#51386: 29.0.50; fido-vertical-mode: ssh host completion

[Gregory Heytings]

> And, beside of fido-vertical-mode, your Tramp patch hides the method 
> names at all.

No, it does not.

> If I try
>
> emacs -Q -l tramp --eval "(setq completion-styles '(flex basic))"
>
> and apply then 'C-x C-f /ss TAB', it offers only the candidate '/sys/', 
> and nothing else. W/o your patch, there are the candidates

Yes, this is because "flex" is tried first, and returns "sys" because it 
contains two "s".

With that setting (flex basic), everything works perfectly with C-x C-f 
/ssh TAB, after which you see "ssh: sshfs: sshx:", and with C-x C-f /ssh: 
TAB, after which you see the hostnames.

With (substring basic), C-x C-f /ss TAB is completed and becomes /ssh.