bug#64846: Emacs 29 RC on Windows: White background color flashes on startup, before background color from config takes effect on Windows

[Yanchi Tóth]

White background color flashes on startup, before background color from
config takes effect in parts of the rectangle occupied by Emacs. Didn't
happen on 28.2, but does happen on both this RC, and the other 29
pretests. See video attachment, and please let me know if I can be of any help.

In GNU Emacs 29.1 (build 2, x86_64-w64-mingw32) of 2023-07-23 built on
 AVALON
Windowing system distributor 'Microsoft Corp.', version 10.0.19045
System Description: Microsoft Windows 10 Pro (v10.0.2009.19045.3208)

Configured using:
 'configure --with-modules --without-dbus --with-native-compilation=aot
 --without-compress-install --with-tree-sitter CFLAGS=-O2'

Configured features:
ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NATIVE_COMP
NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XPM ZLIB

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1252

Major mode: Fundamental

Minor modes in effect:
  ivy-mode: t
  override-global-mode: t
  straight-use-package-mode: t
  straight-package-neutering-mode: t
  straight-symlink-emulation-mode: t
  straight-live-modifications-mode: t
  global-subword-mode: t
  subword-mode: t
  global-auto-revert-mode: t
  delete-selection-mode: t
  electric-pair-mode: t
  global-so-long-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
c:/Users/yanchith/.emacs.d/straight/build/transient/transient hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/transient
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-lint hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-lint
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-jump hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-jump
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-ensure hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-ensure
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-diminish hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-diminish
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-delight hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-delight
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-core hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-core
c:/Users/yanchith/.emacs.d/straight/build/use-package/use-package-bind-key hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/use-package-bind-key
c:/Users/yanchith/.emacs.d/straight/build/bind-key/bind-key hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/use-package/bind-key
c:/Users/yanchith/.emacs.d/straight/build/csharp-mode/csharp-mode hides c:/Users/yanchith/emacs-29.1-rc1/share/emacs/29.1/lisp/progmodes/csharp-mode

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media puny rfc822
mml mml-sec password-cache epa derived epg rfc6068 epg-config gnus-util
time-date 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 counsel xdg xref project byte-opt dired
dired-loaddefs compile text-property-search comint ansi-osc ansi-color
swiper pcase abu-theme wgsl-mode-autoloads glsl-mode-autoloads
csharp-mode-autoloads typescript-mode-autoloads rust-mode-autoloads
counsel-autoloads swiper-autoloads ivy ring ivy-faces ivy-overlay colir
color ivy-autoloads magit-autoloads magit-section-autoloads
git-commit-autoloads with-editor-autoloads transient-autoloads
compat-autoloads expand-region-autoloads multiple-cursors-autoloads
finder-inf edmacro kmacro move-text-autoloads whitespace f-autoloads
dash-autoloads s-autoloads use-package use-package-ensure
use-package-delight use-package-diminish use-package-bind-key bind-key
use-package-core use-package-autoloads bind-key-autoloads
straight-autoloads straight cap-words superword subword autorevert
filenotify easy-mmode delsel comp comp-cstr warnings icons subr-x rx
cl-seq cl-macs gv cl-extra help-mode bytecomp byte-compile elec-pair
hl-line so-long cl-loaddefs cl-lib rmc iso-transl tooltip cconv eldoc
paren electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode
mwheel dos-w32 ls-lisp disp-table term/w32-win w32-win w32-vars
term/common-win tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode lisp-mode prog-mode register
page tab-bar menu-bar rfn-eshadow isearch easymenu timer select
scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors
frame minibuffer nadvice seq simple cl-generic indonesian philippine
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 emoji-zwj charscript
charprop case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure
cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp
files window text-properties overlay sha1 md5 base64 format env
code-pages mule custom widget keymap hashtable-print-readable backquote
threads w32notify w32 lcms2 multi-tty make-network-process
native-compile emacs)

Memory information:
((conses 16 149365 11248)
 (symbols 48 12552 0)
 (strings 32 39098 2504)
 (string-bytes 1 1467890)
 (vectors 16 25019)
 (vector-slots 8 482359 16812)
 (floats 8 124 237)
 (intervals 56 263 0)
 (buffers 984 11))

emacs-flash-of-white.webm
Description: video/webm