Hi,

So I digged into the log and found that `inhibit--record-char' was
obsoleted in bd5c740419.

The reason seems to be that "quail.el" was the last user of this
variable and use it to inhibit a second recording after the first
one. AFAIU, quail.el now have function (quail-add-unread-command-events)
that put a copy of those events with 'no-record into
unread-command-events to have this behaviour.

I was not able to do the same when reading password (there is just one
read_char involved), so as Eli suggested, I choose to un-obsolete
`inhibit--record-char' and use it in `read-passwd' only.