Alex Murray <alex.murray@canonical.com> writes:

> Hi folks,
>
> I have noticed that inline image display doesn't work anymore in
> emacs-29 / git master and have tracked it down to a change to the way
> mm-inline-image inserts an image into the buffer.
>
> In
> https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=d2186160a9e978960c0f96bc3b4fc65b5affc170
> mm-inline-image was changed to use insert-image instead of
> put-image. This inserts the image into the buffer using a single space
> as the string contents with a display property set as the image contents
> so that the single space is not shown itself but instead the image is
> shown in its place.
>
> I had thought the culprit then was the use of
> notmuch-wash-elide-blank-lines within the default value of
> notmuch-show-insert-text/plain-hook - assuming that since the line
> containing the image is now just a single space, it then gets deleted
> from the buffer and the image is never shown. However, even after
> setting notmuch-show-insert-text/plain-hook to nil, images are still not
> shown inline by notmuch.
>
> However, if I locally redefine mm-inline-image to use say a period "."
> as the string argument to insert-image then the image appears as
> expected.
>
> Any thoughts on what may be happening here and how best to resolve this?
>

The problem seems to be the call to indent-rigidly in
notmuch-show-lazy-part. The image is actually inserted OK, but then
apparently deleted by indent-rigidly (probably because it looks like
whitespace).

I tried replacing indent-rigidly with a simplified version the and that
leaves the image inserted, but unfortunately doesn't indent it
properly. If you want to play with it, my half working patch is
attached.