browse-url-mail is an interactive autoloaded compiled Lisp function in `browse-url.el'.

(browse-url-mail URL &optional NEW-WINDOW)

Open a new mail message buffer within Emacs for the RFC 2368 URL.
Default to using the mailto: URL around or before point as the
recipient's address. Supplying a non-nil interactive prefix argument
will cause the mail to be composed in another window rather than the
current one.

When called interactively, if variable `browse-url-new-window-flag' is
non-nil use `compose-mail-other-window', otherwise `compose-mail'. A
non-nil interactive prefix argument reverses the effect of

When called non-interactively, optional second argument NEW-WINDOW is
used instead of `browse-url-new-window-flag'.