x11vnc mirrors :0, but with no monitor attached the connector has no EDID and no
CRTC, so GNOME renders nothing and the remote desktop is black. Reproduced the
hard way on this box: the desktop only worked because the session had started
while a screen was plugged in, and survived exactly until the next restart.
The step captures a connected monitor's EDID, installs it as
drm.edid_firmware with video=<connector>:1920x1080e so the connector reports
permanently attached, and adds a login-time hook to raise the resolution — the
replayed EDID's *preferred* mode is the captured panel's native one, which can be
tiny, and GNOME picks preferred. monitors.xml is the documented override but its
monitor matching did not take.
The EDID can only be captured from a screen that is plugged in, so a headless run
skips with instructions rather than pretending to succeed. Re-running is safe:
GRUB is left alone once the argument is present, and the mode setter no-ops when
the mode is already right.
officer-set-display.sh discovers the output and the largest mode within a cap
rather than hardcoding either, since setup runs before X exists and cannot know
them.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
