OrgMsg is a GNU Emacs global minor mode mixing up Org mode and your Mail User Agent Mode (Message mode, mu4e mode, or notmuch mode) to compose and reply to emails in a Outlook HTML friendly style.

Presentation

Not that I really like the Outlook email style but in a work environment dominated by this email client, it is good to be able to reply with the same style. By default, if the original message is in plain text OrgMsg keeps it that way and does not activate itself. It allows to reply to developer mailing list (or any real technical people who knows how to handle text email) seamlessly. This behavior can customized as documented in the Configuration section below. If the original message is in the HTML form, it activates the OrgMsg mode on the reply buffer.

OrgMsg provides a org-msg-edit-mode which is an derivation of Org mode in which some functionality of the current Mail User Agent (Message mode, mu4e mode, or notmuch mode) are imported or replicated. For instance, a OrgMsg buffer uses the same font-lock-keywords than Message mode or the TAB key while the cursor is in the header calls the message-tab function.

For convenience, the original message is quoted below the --citation follows this line (read-only)-- marker. So you can easily refer to the original message. However, the entire quoted text is read-only because OrgMsg does not support modification of the original content.

OrgMsg has a mechanism to support different Mail User Agents (message, mu4e, notmuch …). Each function which depends on the Mail User Agent calls org-msg-mua-call function which is an indirection to the OrgMsg Mail User Agent specific function.

Outlook email are really poor compared to what can be achieved by Org mode. I personally use the #+{begin|end}_quote to quote part of the email I am replying to. I extensively make use of #+{begin|end}_src mode to provide extract of code or example of changes, I sometimes use Org babel to generate an on the fly sequence diagram (using plantuml) or a simple graph (using dot).

Keys and interactive functions

The OrgMsg mode keys are the usual key combination used in either Org mode or Message mode.

• C-c C-e – calls org-msg-preview which generate and display the exported version of the email
• C-c C-k – calls message-kill-buffer
• C-c C-s – calls message-goto-subject (same as in Message mode)
• C-c C-b – calls org-msg-goto-body (similar to message-goto-body in Message mode)
• C-c C-a – calls org-msg-attach, very similar to the org-attach function. It lets you add or delete attachment for this email. Attachment list is stored in the :attachment: property.
• C-c C-c – calls org-ctrl-c-ctrl-c. OrgMsg configures org-msg-ctrl-c-ctrl-c as a final hook of Org mode. When org-msg-ctrl-c-ctrl-c is called in a OrgMsg buffer it generates the MIME message, sends it and exits. If the universal argument is supplied, the last step is skipped.

The org-msg-mode interactive function can be called to enable/disable OrgMsg. By default, once the module is loaded, it is disable. If you want to reply to an email without making use of OrgMsg, you should call that function before you call the reply-to function.

To start composing a new OrgMsg email, you can call the interactive message-mail function. If your mail-user-agent is message-user-agent (which is the by default Emacs configuration), compose-mail calls message-mail and is bound to [C-x m] by default.

Configuration

OrgMsg depends on this module: emacs-htmlize

The default Emacs Mail User Agent is Message, if you are a mu4e user, you need to define your mail user agent (see mu4e documentation - Emacs-default) because OrgMsg places some hooks and runs specific functions depending on the current Mail User Agent. The proper Mail User Agent should be defined before you activate OrgMsg (call the org-msg-mode function). Here is how you can define the Mail User Agent mu4e.

(setq mail-user-agent 'mu4e-user-agent)

The following is my configuration which you can use as an example.

 (setq mail-user-agent 'gnus-user-agent)
 (require 'org-msg)
 (setq org-msg-options "html-postamble:nil H:5 num:nil ^:{} toc:nil author:nil email:nil \\n:t"
	org-msg-startup "hidestars indent inlineimages"
	org-msg-greeting-fmt "\nHi%s,\n\n"
	org-msg-recipient-names '(("jeremy.compostella@gmail.com" . "Jérémy"))
	org-msg-greeting-name-limit 3
	org-msg-default-alternatives '((new		. (text html))
				       (reply-to-html	. (text html))
				       (reply-to-text	. (text)))
	org-msg-convert-citation t
	org-msg-signature "

 Regards,

 #+begin_signature
 --
 *Jeremy*
 /One Emacs to rule them all/
 #+end_signature")
 (org-msg-mode)

The org-msg-greeting-fmt can be customized to configure the default greeting message. If this format contains a %s token it is automatically replaced with the name of the person you are replying to with a space prefix. The name is either the recipient name specified in the org-msg-recipient-names list or the first name automatically extracted from the email address. If org-msg-greeting-fmt-mailto is t, the name is formatted as mailto link.

The types of MIME alternatives that are sent can be modified by editing the :alternatives: property on each message. For example, setting this property to (text html) will send both text and HTML alternatives to your message, whereas (html) or (text) will just send HTML or plain text respectively.

The default value of the :alternatives: property can be set with the org-msg-default-alternatives customization variable. It is associative list which value is a list of alternatives and the key is one of the following:

• new for a new email
• reply-to-html for a reply to an HTML email
• reply-to-text for a reply to a plain text email

If one of these keys is not present OrgMsg does not activate for this type of email.

If you want to add your own custom exporters, this can be done by modifying org-msg-alternative-exporters.

Alternatives list should be placed in increasing order of preference to meet RFC-1341 section 7.2.3 guidelines.

OrgMsg composes reply to HTML emails in top-posting style. This behavior can be disabled by setting org-msg-posting-style to any value other than top-posting.

The original HTML message generated by gnus includes fields such as From and To. Unfortunately, some less desirable field like attachment are sometimes added. These fields can be listed in org-msg-undesirable-headers to be automatically removed by OrgMsg.

In order to avoid CSS conflict, OrgMsg performs inline replacement when it generates the final HTML message. See the org-msg-enforce-css variable to customize the style (and the default org-msg-default-style variable for reference).

Setting the org export option tex:dvipng or tex:dvisvgm is handeled correctly by this mode by producing inline images or inlining the generated SVG. Note that most mailclients however sadly do not display SVG content in mails so it might be best to stick to settings producing images unless you know your recipient’s mailclient supports SVG.

OrgMsg includes a minimalist detection of missing attachment which relies on a regular expression defined by the org-msg-attached-file-reference customization variable.

Advanced configuration

It would be impossible for OrgMsg to offer composition customization variables to accommodate all the combinations of desirable behaviors. For instance, one could want to reply as plain text only for a certain type of email as characterized by the sender domain name or a subject prefix. Or another could want to change its signature when replying as plain text only. In addition, emails can be used to interact with machines and their protocol can have even more exotic requirements.

To offer plenty of flexibility without turning OrgMsg into an unsustainable project, OrgMsg implements the two following and well documented functions. They are called at composition time by the org-msg-post-setup function with the new message as the current buffer. They can be advised by the end-user to implement any particular behavior (cf. Advising Emacs Lisp Functions).

• org-msg-get-alternatives(type) returns the list of alternatives
• org-msg-composition-parameters (type alternatives) returns the posting style, greeting format and signature

For example, here is how I configure OrgMsg to dynamically change my greeting message and signature when I reply as a plain text.

 (defun my-org-msg-composition-parameters (orig-fun &rest args)
   "Tweak my greeting message and my signature when replying as
   plain/text only."
   (let ((res (apply orig-fun args)))
     (when (equal (cadr args) '(text))
	(setf (alist-get 'greeting-fmt res) "\n")
	(setf (alist-get 'signature res)
	      (replace-regexp-in-string "\\([\*/]\\|\nRegards,\n\n\\)" ""
					org-msg-signature)))
     res))
 (advice-add 'org-msg-composition-parameters
	      :around #'my-org-msg-composition-parameters)

Quotes

Org mode supports quotes using quote blocks. The Org mode HTML backend exports such blocks as blockquote HTML tags and OrgMsg will apply a CSS style on top of it. Unfortunately, the Org mode engine does not allow nested quote blocks.

OrgMsg supports nested quotes with special #+{begin|end}_quote[0-9]+ blocks. A #+{begin|end}_quote1 block can be nested in a #+{begin|end}_quote block, a #+{begin|end}_quote2 block can be nested in a #+{begin|end}_quote1 block … In order to ease the identification of the different levels of quotes once exported to HTML, each level uses a different color.

Using #+{begin|end}_quote[0-9]+ can be cumbersome and as thus, OrgMsg also supports the automatic conversion of the well established ASCII quote form based on the > characters. For instance, if the org-msg-convert-citation customization variable is set to t, the following text will be automatically converted to multi-level quote blocks before being exported to HTML.

> quote an email
>> which had quoted another email
>>> which had quoted another email

And it will look like this.