One various OSes, Emacs ships with site-lisp files that load
OS/architecture-specific config (like native-comp config), or load-lines
for Emacs packages installed via your OS package manager (like mu4e).
Output from these are rarely suppressed, for some reason, which causes
noise in *Messages* at startup, which triggers a redraw, which can be
very expensive during startup, depending on your window system.
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