bug#62935: 29.0.90; icomplete-vertical-mode misses add-file-local-variable alternative

[Van Ly]

> Date: Tue, 18 Apr 2023 18:53:01 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 62935@debbugs.gnu.org
> 
> 
> add-file-local-variable completes only on variables that are safe as
> local variables, and buffer-save-without-query is not.  So you need to
> type its name completely.
> 

I see why.  Maybe unsafe options can allow an override to appear in
grey faded font.  There could be an explainer dialogue for what is unsafe.

I use buffer-save-without-query on scratch files.