Stefan Monnier <monnier@iro.umontreal.ca> writes:
> If it's not for everyone, then it should arguably be provided under the
> control of the config var, but that doesn't mean it should be in
> a separate package or relegated to some ELisp snippets for people to
> copy&paste into their init file.
>
> Whether it better belongs alongside `isearch` or `isearch-mb` will
> probably depend on details of how it's implemented.

Here's a patch providing just that for isearch. It could be added to
isearch-mb almost just as easily though it has nothing to do with search
entry.

With regards to an isearch-mb wiki "trick": the same result could be
achieved using `isearch-mode-end-hook` and :after advice on
`isearch-message`.

Whether it becomes a part of isearch or not some feedback would be
appreciated (;

1. Is it right to modify `isearch-lazy-count-format` in this way to
reduce code in `isearch-show-lazy-count-at-match`?

2. Is it right to add a new face for this and if so does this need to be
included in NEWS or other documentation?

3. Should it be extended to allow for custom positioning of the overlay?
Perhaps with a variable like `isearch-lazy-count-at-match-pos-function`?

-- 
Thanks,
Jai