bug#67393: 29.1; Slow to open file if autosave exists

[Juri Linkov]

>>> This is indeed not a bug, but I am wondering if it would be better to
>>> utilize `set-multi-message' somehow. We are certainly able to display
>>> multiple recent messages in the echo area. Then, why not allow to keep
>>> more important ones visible for a time period without blocking?
>>
>> It's not easy to temporarily enable `set-multi-message',
>> since it's not clear at what moment to disable it afterwards.
>
> What I meant is to change the default `set-message-function' in such a
> way that it displays "important" messages for a custom time period, in
> addition to the last message.

I agree.  The most annoying delay is in 'ispell-parse-output':

    (ding) ; error message from ispell!
    (message "Ispell error: %s" output)
    (sit-for 5)

So I need to waste 5 seconds several times during spell-checking.

It would be nicer to prepend this error message to any last displayed
message during these 5 seconds.