These days, many e-mail messages contain rich-text (typically, HTML); either as an alternative to a text-only version, or even as the only option.
By default, mu4e tries to display the ’richest’ option, which is the
last MIME-part of the alternatives. You can customize this to prefer
the text version, if available, with something like the following in
your configuration (and see the docstring for
mm-discouraged-alternatives
for details):
(with-eval-after-load "mm-decode" (add-to-list 'mm-discouraged-alternatives "text/html") (add-to-list 'mm-discouraged-alternatives "text/richtext"))
When displaying rich-text messages inline, mu4e
(through gnus
)
uses the shr
built-in HTML-renderer. If you’re using a dark color
theme, and the messages are hard to read, it can help to change the
luminosity, e.g.:
(setq shr-color-visible-luminance-min 80)
Note that you can switch between the HTML and text versions by clicking on the relevant part in the messages headers; you can make it even clearer by indicating them in the message itself, using:
(setq gnus-unbuttonized-mime-types nil)
When you run Emacs in graphical mode, by default images attached to messages are shown inline in the message view buffer.
To disable this, set gnus-inhibit-images
to t
. By default,
external images in HTML are not retrieved from external URLs because
they can be used to track you.
Apart from that, you can also control whether to load remote images; since loading remote images is often used for privacy violations, by default this is not allowed.
You can specify what URLs to block by setting
gnus-blocked-images
to a regular expression or to a function
that will receive a single parameter which is not meaningful for
mu4e
.
For example, to enable images in Github notifications, you could use the following:
(setq gnus-blocked-images (lambda(&optional _ignore) (if (mu4e-message-contact-field-matches (mu4e-message-at-point) :from "notifications@github.com") nil ".")))
mu4e
inherits the default gnus-blocked-images
from Gnus and
ensures that it works with mu4e
too. However, mu4e is not Gnus, so
if you have Gnus-specific settings for gnus-blocked-images
, you
should verify that they have the desired effect in mu4e
as
well.