This patch should not change behavior. It typically omits backslashes
where they are redundant (e.g., in the string literal "^\$").
In a few places, insert backslashes where they make regular
expressions clearer: e.g., replace "^\*" (equivalent to "^*") with
"^\\*", which has the same effect as a regular expression.
Also, use ‘\ %’ instead of ‘\%’ when avoiding confusion with SCCS IDs,
and similarly use ‘\ $’ instead of ‘\$’ when avoiding confusion with
RCS IDs, as that makes it clearer that the backslash is intended.
* lisp/mail/mailclient.el (mailclient-send-it):
Also fix the case when mailclient-place-body-on-clipboard-flag
is non-nil. Problem reported by Eli Zaretskii (Bug#21471#37).
* lisp/mail/mailclient.el (mailclient-encode-string-as-url):
Use RFC 6068’s list of unreserved characters.
(mailclient-send-it): When encoding the body as a URL,
first decode it as per Content-Type: and Content-Transfer-Encoding:,
as URLs must use percent-encoded UTF-8 (Bug#21471).
* doc/misc/url.texi (mailto): Update RFC number.