Monorepo for Aesthetic.Computer
aesthetic.computer
install-firmware.sh: wrap MrChromebox ROM with AC splash + boot tweaks
Hosted at https://aesthetic.computer/install-firmware.sh — one-liner to
install MrChromebox's UEFI firmware on a supported Chromebook with the
aesthetic.computer boot splash baked in.
curl -fsSL https://aesthetic.computer/install-firmware.sh | sudo bash
The script doesn't re-build coreboot; it inherits MrChromebox's signed
per-board ROMs and just swaps bootsplash.bmp inside CBFS via cbfstool,
then flashes with flashrom. Upstream firmware fixes flow through
automatically on every re-run.
Also shortens etc/boot-menu-wait to 500ms (stock is 2500ms) so the
splash doesn't linger. A backup of the current firmware is written to
/tmp/firmware-backup-<ts>.rom before anything gets written.
Assets the script downloads from /firmware/:
- ac-splash.bmp 1366x768 24-bit BMP replacing the MrChromebox rabbit
- cbfstool static-linked coreboot CBFS editor
TODO (follow-up):
- Commit the actual ac-splash.bmp and cbfstool binary assets.
- Board auto-detect works on ChromeOS-style firmware (crossystem +
DMI). Add a fallback for coreboot/edk2 where neither is reliable.
- Provide a --restore flag that writes the nearby
BACKUP-*-Google_*.rom file if present on the USB.
Docs referenced:
- https://docs.mrchromebox.tech/docs/firmware/
- https://doc.coreboot.org/util/cbfstool/index.html
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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system/public/_headers
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system/public/_headers
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Access-Control-Allow-Origin: *
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Cache-Control: no-cache, no-store, must-revalidate
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Pragma: no-cache
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Expires: 0
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Expires: 0
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# Firmware install script + assets — served as text/plain or
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# application/octet-stream so `curl | bash` and raw binary downloads
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# both work without content negotiation surprises.
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/install-firmware.sh
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Content-Type: text/plain; charset=utf-8
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Cache-Control: public, max-age=60
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/firmware/*
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Cache-Control: public, max-age=3600
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system/public/firmware/README.md
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system/public/firmware/README.md
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# Firmware customization assets
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Files referenced by [`/install-firmware.sh`](../install-firmware.sh):
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- `ac-splash.bmp` — 1366×768 24-bit BMP that replaces the MrChromebox
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rabbit at boot. Must be uncompressed BMP (coreboot's splash decoder
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is minimal); generated from `system/scripts/firmware-splash.mjs`.
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- `cbfstool` — statically-linked linux-x86_64 binary used to edit the
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coreboot CBFS of the downloaded base ROM. Upstream build recipe
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lives at https://doc.coreboot.org/util/cbfstool/index.html.
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Pipeline:
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1. `install-firmware.sh` downloads the board's signed ROM from
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MrChromebox's CDN.
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2. Downloads `ac-splash.bmp` + `cbfstool` from here.
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3. Swaps the splash and tweaks `etc/boot-menu-wait` inside CBFS.
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4. Flashes the composed ROM via `flashrom -p internal -w`.
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Both assets are published by `npm run firmware:publish` (TODO).
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system/public/install-firmware.sh
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system/public/install-firmware.sh
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#!/usr/bin/env bash
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# install-firmware.sh — install a MrChromebox UEFI firmware with the
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# aesthetic.computer boot splash baked in.
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#
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# Usage (from a ChromeOS developer shell or from ac-native's prompt):
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#
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# curl -fsSL https://aesthetic.computer/install-firmware.sh | sudo bash
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#
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# This does NOT re-build coreboot — we inherit Mr Chromebox's signed
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# per-board ROM from https://mrchromebox.tech/ and only swap the
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# bootsplash.bmp inside CBFS with our own. Upstream firmware fixes flow
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# through automatically on each re-run.
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#
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# Docs we follow:
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# https://docs.mrchromebox.tech/docs/firmware/
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# https://doc.coreboot.org/util/cbfstool/index.html
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#
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# Safety:
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# 1. Always backs up current firmware to /tmp/firmware-backup-<ts>.rom
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# AND echoes the path so the user can copy it to a USB before reboot.
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# 2. Refuses to flash unless `flashrom` is able to read the chip and
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# the signed ROM we composed is the expected size.
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# 3. `--dry-run` skips the final `flashrom -w` so you can inspect the
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# composed ROM first.
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set -euo pipefail
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AC_CDN="${AC_CDN:-https://aesthetic.computer}"
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MRC_CDN="${MRC_CDN:-https://mrchromebox.tech/files/firmware/full_rom}"
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WORK="${WORK:-/tmp/ac-firmware.$$}"
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DRY_RUN="${DRY_RUN:-0}"
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log() { printf "\033[0;36m[ac-fw]\033[0m %s\n" "$*"; }
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err() { printf "\033[0;31m[ac-fw]\033[0m %s\n" "$*" >&2; }
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die() { err "$*"; exit 1; }
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for arg in "$@"; do
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case "$arg" in
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--dry-run) DRY_RUN=1 ;;
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--help|-h)
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sed -n '2,20p' "$0" | sed 's/^# \{0,1\}//'
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exit 0 ;;
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esac
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done
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[ "$(id -u)" = "0" ] || die "Must run as root (use sudo)."
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mkdir -p "$WORK"
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trap 'rm -rf "$WORK"' EXIT
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# ── 1. Detect board ────────────────────────────────────────────────
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log "Detecting board…"
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BOARD=""
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if command -v crossystem >/dev/null 2>&1; then
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# ChromeOS-style — most reliable on stock + MrChromebox firmware.
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BOARD=$(crossystem hwid 2>/dev/null | awk '{print tolower($1)}' | cut -d- -f1)
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fi
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if [ -z "$BOARD" ] && [ -f /sys/class/dmi/id/product_name ]; then
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BOARD=$(tr -d '\0\n' < /sys/class/dmi/id/product_name | tr '[:upper:] ' '[:lower:]_' | cut -d. -f1)
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fi
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[ -n "$BOARD" ] || die "Could not detect board. Set BOARD=<name> and re-run."
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log " board: $BOARD"
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# ── 2. Tools ───────────────────────────────────────────────────────
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# Mr Chromebox's script already installs flashrom; we need cbfstool too.
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# Ship a static-linked cbfstool on our CDN so ac-native's minimal busybox
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# init doesn't need a full coreboot toolchain to get this working.
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need() { command -v "$1" >/dev/null 2>&1 || return 1; }
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fetch() {
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local url="$1" out="$2"
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curl -fsSL --retry 3 -o "$out" "$url" \
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|| die "Download failed: $url"
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}
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if ! need flashrom; then
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die "flashrom not installed. On ChromeOS dev shell: 'sudo pacman -Sy flashrom' or install via your distro."
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fi
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CBFSTOOL="$WORK/cbfstool"
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if need cbfstool; then
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cp "$(command -v cbfstool)" "$CBFSTOOL"
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else
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log "Fetching cbfstool from $AC_CDN/firmware/cbfstool…"
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fetch "$AC_CDN/firmware/cbfstool" "$CBFSTOOL"
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chmod +x "$CBFSTOOL"
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fi
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"$CBFSTOOL" -h >/dev/null 2>&1 || die "cbfstool unusable — try reinstalling."
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# ── 3. Download base ROM from MrChromebox ─────────────────────────
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BASE_ROM="$WORK/base.rom"
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MRC_URL="$MRC_CDN/coreboot_tiano-$BOARD-mrchromebox.rom"
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log "Fetching MrChromebox ROM for '$BOARD'…"
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fetch "$MRC_URL" "$BASE_ROM"
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BASE_SIZE=$(stat -c%s "$BASE_ROM")
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log " size: $((BASE_SIZE / 1024 / 1024))MB ($BASE_SIZE bytes)"
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# ── 4. Apply aesthetic.computer customizations ────────────────────
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AC_ROM="$WORK/ac.rom"
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cp "$BASE_ROM" "$AC_ROM"
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# Swap the bootsplash. BMP must be 1366x768 24/32-bit uncompressed
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# (coreboot's splash decoder is minimal). AC ships a pre-baked copy at
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# /firmware/ac-splash.bmp — overrideable via env SPLASH_URL.
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SPLASH_URL="${SPLASH_URL:-$AC_CDN/firmware/ac-splash.bmp}"
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if curl -fsSL --head "$SPLASH_URL" >/dev/null 2>&1; then
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SPLASH="$WORK/splash.bmp"
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log "Fetching splash: $SPLASH_URL"
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fetch "$SPLASH_URL" "$SPLASH"
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"$CBFSTOOL" "$AC_ROM" remove -n bootsplash.bmp 2>/dev/null || true
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"$CBFSTOOL" "$AC_ROM" add -f "$SPLASH" -n bootsplash.bmp -t raw
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log " ✓ swapped bootsplash.bmp"
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else
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log " splash not available at $SPLASH_URL — skipping (keeping MrChromebox rabbit)."
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fi
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# Shorten the boot-menu wait. Upstream default is 2500ms; we want 500ms.
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"$CBFSTOOL" "$AC_ROM" add-int -i 500 -n etc/boot-menu-wait 2>/dev/null \
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|| log " (could not set etc/boot-menu-wait; continuing)"
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# Verify size didn't change.
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AC_SIZE=$(stat -c%s "$AC_ROM")
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[ "$AC_SIZE" = "$BASE_SIZE" ] || die "Size mismatch after customization: $AC_SIZE vs $BASE_SIZE."
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log " customized ROM size OK"
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# ── 5. Backup current firmware ────────────────────────────────────
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BACKUP="/tmp/firmware-backup-$(date +%Y%m%d-%H%M%S).rom"
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log "Backing up current firmware → $BACKUP"
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flashrom -p internal -r "$BACKUP" 2>&1 | grep -vE "^(flashrom|Calibrating)" || true
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[ -s "$BACKUP" ] || die "Backup read failed — refusing to flash."
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log " ✓ backup saved ($(du -h "$BACKUP" | cut -f1))"
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# ── 6. Flash ──────────────────────────────────────────────────────
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if [ "$DRY_RUN" = "1" ]; then
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log "DRY_RUN=1 — stopping before flash."
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log " composed ROM: $AC_ROM"
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log " current backup: $BACKUP"
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exit 0
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fi
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log "Flashing customized ROM…"
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flashrom -p internal -w "$AC_ROM" 2>&1 | grep -vE "^(Calibrating|Reading old|Erasing|Writing)" || true
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log "✅ Done. Reboot when ready — new splash takes effect next boot."
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log " backup: $BACKUP"