bug#43470: 27.1; Drag and Drop not working properly in 27.1 on OSX

[Paul Magwene, Ph.D.]

* Drag and drop events no longer appear to work properly in Emacs 27.1 on
Mac OS X.

* When I run Emacs from the command line I see the message: `Invalid data
type in dragging pasteboard` when trying to drag text or URLs from a webbrowser
(firefox or safari) into an Emacs buffer.

* I've tested this with two different builds of 27.1 -- from
https://emacsformacosx.com and the "emacs plus" formula under homebrew
(https://github.com/d12frosted/homebrew-emacs-plus) on both OS X 10.14.6
(Mavericks) and 10.15.6 (Catalina)

* Reverting to Emacs 26.3 resolves this issue


In GNU Emacs 27.1 (build 1, x86_64-apple-darwin19.5.0, NS appkit-1894.50 
Version 10.15.5 (Build 19F101))
of 2020-08-27 built on d12frosted.local
Windowing system distributor 'Apple', version 10.3.1894
System Description:  Mac OS X 10.15.6

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Composing main Info directory...done
Beginning of buffer [18 times]
Mark saved where search started
Beginning of buffer [24 times]
Making completion list...
user-error: End of history; no default available

Configured using:
'configure --disable-dependency-tracking --disable-silent-rules
--enable-locallisppath=/usr/local/share/emacs/site-lisp
--infodir=/usr/local/Cellar/emacs-plus@27/27.1/share/info/emacs
--prefix=/usr/local/Cellar/emacs-plus@27/27.1 --with-xml2 --with-gnutls
--without-dbus --with-imagemagick --with-modules --with-rsvg --with-ns
--disable-ns-self-contained'

Configured features:
RSVG IMAGEMAGICK GLIB NOTIFY KQUEUE ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS NS MODULES THREADS JSON PDUMPER LCMS2 GMP

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs
format-spec rfc822 mml mml-sec password-cache epa derived epg epg-config
gnus-util rmail rmail-loaddefs text-property-search seq byte-opt gv
bytecomp byte-compile cconv mm-decode mm-bodies mm-encode mail-parse
rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045
ietf-drums mm-util mail-prsvr mail-utils thingatpt jka-compr time-date
subr-x misearch multi-isearch info help-mode easymenu cl-loaddefs cl-lib
tooltip eldoc electric uniquify ediff-hook vc-hooks lisp-float-type
mwheel term/ns-win ns-win ucs-normalize mule-util term/common-win
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode elisp-mode lisp-mode prog-mode register page
tab-bar menu-bar rfn-eshadow isearch timer select scroll-bar mouse
jit-lock font-lock syntax facemenu font-core term/tty-colors frame
minibuffer cl-generic cham georgian utf-8-lang misc-lang vietnamese
tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
composite charscript charprop case-table epa-hook jka-cmpr-hook help
simple abbrev obarray cl-preloaded nadvice loaddefs button faces
cus-face macroexp files text-properties overlay sha1 md5 base64 format
env code-pages mule custom widget hashtable-print-readable backquote
threads kqueue cocoa ns lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 77707 9630)
(symbols 48 6474 1)
(strings 32 20721 1816)
(string-bytes 1 627785)
(vectors 16 11181)
(vector-slots 8 157770 17782)
(floats 8 31 51)
(intervals 56 4895 0)
(buffers 1000 15))


Paul Magwene
Associate Professor
Department of Biology
Duke University