some issues with emacs 25

[Matthew Lear]

Hi,
I switched to trying emacs 25 (25.1) with notmuch the other day. I
really like some of the improvements that have been made (in particular,
SHR seems to do a much nicer and quicker job of rendering html emails).
However, things came a little unstuck when I tried to reply to an email
with notmuch. I have notmuch set to discourage plain text simply because
I deal with a lot of email which is sent in html (people frequently
in-line tables, images etc) and when I replied, notmuch generated the
following in the new message buffer:

> !!! Bodypart handler `notmuch-show-insert-part-text/html' threw an error:
> !!! Window is dedicated to ‘*unsent mail to user at domain.com*’
>

Errors like these are generated by replying from either notmuch-tree or
notmuch-show.

I'd made no changes to my .emacs before switching to 25 and just to
check, I switched back to 24 (24.5) and I could reply to the same email
without any trouble.

I'm of the opinion that this is probably some sort of set up /
configuration issue specific to 25, but I'm quite surprised. I don't
have many settings for handling html stuff:

(setq mm-text-html-renderer 'shr)
(setq shr-inhibit-images nil)
(setq mime-view-text/html-previewer 'shr)
(setq mm-inline-text-html-with-images t)
(setq notmuch-multipart/alternative-discouraged '("text/plain"))

Is this reproducible for anyone else with notmuch from git/master as of
today?

Cheers,
--  Matt