[mu4e bug] Reply to sender (only) does not work

[Chris00]

Describe the bug & How to Reproduce

Reply to any message with “reply to sender only” and all addresses end up in To.

In the function

(defun mu4e~draft-create-to-lst (origmsg)
  "Create a list of address for the To: in a new message.
This is based on the original message ORIGMSG. If the Reply-To
address is set, use that, otherwise use the From address. Note,
whatever was in the To: field before, goes to the Cc:-list (if
we're doing a reply-to-all). Special case: if we were the sender
of the original, we simple copy the list form the original."
  (let* ((reply-to
         (append
          (plist-get origmsg :to)
          (or (plist-get origmsg :reply-to) (plist-get origmsg :from))))
         (reply-to (cl-delete-duplicates reply-to
                                         :test #'mu4e~draft-address-cell-equal)))
    (if mu4e-compose-dont-reply-to-self
        (cl-delete-if
         (lambda (to-cell)
           (mu4e-personal-address-p (mu4e-contact-email to-cell)))
         reply-to)
      reply-to)))

I do not understand the (plist-get origmsg :to) because it will put all addresses in To regardless of whether one wants to replay to all or not.

Environment
Debian,
mu commit 6168d77

Checklist

• you are running either an 1.8.x/1.10.x release or master (otherwise please upgrade)
• you can reproduce the problem without 3rd party extensions (including Doom/Evil, various extensions etc.)
• you have read all of the above