* mu4e-compose: invoke mu4e-compose-mode only when the message is complete;

this allows for more useful mu4e-compose-mode hooks

emacs/mu4e-compose.el

@@ -487,14 +487,14 @@ or `mu4e~compose-newmsg-construct'. The editing buffer is using
 Gnus' `message-mode'."
   (unless mu4e-maildir       (error "mu4e-maildir not set"))
   (unless mu4e-drafts-folder (error "mu4e-drafts-folder not set"))
-  (let ((draft
+  (let ((inhibit-read-only t)
+	 (draft
 	  (if (member compose-type '(reply forward new))
 	    (mu4e~compose-open-new-draft-file compose-type original-msg)
 	    (if (eq compose-type 'edit)
 	      (plist-get original-msg :path)
 	      (error "unsupported compose-type %S" compose-type)))))
     (find-file draft)
-    (mu4e-compose-mode)
     ;; insert mail-header-separator, which is needed by message mode to separate
     ;; headers and body. will be removed before saving to disk
     (mu4e~compose-insert-mail-header-separator)
@@ -529,6 +529,10 @@ Gnus' `message-mode'."
   ;; buffer is not user-modified yet
   (mu4e~compose-set-friendly-buffer-name compose-type)
   (set-buffer-modified-p nil)
+
+  ;; set compose mode -- so now hooks can run
+  (mu4e-compose-mode)
+
   ;; now jump to some use positions, and start writing that mail!
   (if (member compose-type '(new forward))
     (message-goto-to)