On macOS, it doesn’t seem to be possible to specify an `initial-frame-alist` that starts Emacs in “non-native” fullscreen mode (i.e., without the system animation and taking up a separate Space in Mission Control). To see the difference, use `toggle-frame-fullscreen` which has the desired behavior. This can be compared with clicking the green fullscreen icon on the window, which will use the system fullscreen. On the emacs-mac port by Yamamoto Mitsuharu, it’s possible to specify the following to start in this mode:

```
(setq initial-frame-alist '((fullscreen . fullboth)))
```

However, both this and `(setq initial-frame-alist '((fullscreen . fullscreen)))` do not have this effect on the main build of Emacs. They always use the system fullscreen.

Michael

In GNU Emacs 27.0.90 (build 1, x86_64-apple-darwin18.7.0, NS appkit-1671.60 Version 10.14.6 (Build 18G3020))
 of 2020-03-01 built on mks.local
Repository revision: b42b894d1def7180ab715615116fe6af65b76bd8
Windowing system distributor 'Apple', version 10.3.1671
Recent messages:
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evil-line-move: End of buffer [6 times]
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Mark activated

Configured using:
 'configure --disable-dependency-tracking --disable-silent-rules
 --enable-locallisppath=/usr/local/share/emacs/site-lisp
 --infodir=/usr/local/Cellar/emacs-plus/HEAD-b42b894/share/info/emacs
 --prefix=/usr/local/Cellar/emacs-plus/HEAD-b42b894 --with-xml2
 --without-dbus --with-gnutls --with-imagemagick --with-json
 --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 $LC_ALL: en_US.UTF-8
 value of $LANG: en_US.UTF-8
 locale-coding-system: utf-8

Major mode: Org

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 vi-tilde-fringe-mode: t
 goto-address-mode: t
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 save-place-mode: t
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 async-bytecomp-package-mode: t
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 solaire-global-mode: t
 solaire-mode: t
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 undo-tree-mode: t
 shell-dirtrack-mode: t
 evil-mode: t
 evil-local-mode: t
 +popup-mode: t
 ns-auto-titlebar-mode: t
 general-override-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
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 font-lock-mode: t
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 size-indication-mode: t
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Load-path shadows:
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Memory information:
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