Thanks for looking into this. Requested info attached:

- journal.txt — `journalctl -b0` from a fresh boot today (no leak yet, uptime 
only minutes).
- journal-boot-with-leak-2026-10-10_12.txt.xz — full journal of the boot where 
the leak happened
  (2026-10-10 17:35 → 2026-10-12 14:34, +07), containing the repeated OOM kills 
of gnome-shell.
- packages.txt — `dpkg -l`
- settings.txt — `dconf dump /org/gnome/shell/`
- hotplug.log — my own logger: every DP-1/HDMI-A-1 connector status/DPMS change 
as it happens, plus
  a MEM line once a minute (MemAvailable, Shmem from /proc/meminfo, compositor 
RSS, count of
  "Cursor update failed" messages; "phút" = minute). It shows DP-1 flapping 
connected/disconnected ~470-520 times/hour
  while DPMS is off, with Shmem rising ~25 GB/h until OOM, and Shmem being 
released when the
  screens wake.

System: Ubuntu 26.04.1, Intel Alder Lake-S UHD 730 (i915), mesa 
26.0.8-1ubuntu0.3,
mutter 50.1-0ubuntu2.4, gnome-shell 50.1-0ubuntu1.3. Monitors: LG UltraGear on 
DP-1, generic HDMI
panel on HDMI-A-1.

Regarding the other points:

* Local extensions: ~/.local/share/gnome-shell/extensions does not exist — I 
only have the
  default Ubuntu system extensions (ding, ubuntu-dock, ubuntu-appindicators, 
tiling-assistant,
  snapd-prompting, snapd-search-provider, web-search-provider).

* Bug 2143073: possibly related, since this is i915 and the leaking memory is 
Shmem. But note that
  after my user session was OOM-killed (2026-10-10 21:47), the leak continued 
in the *GDM greeter*
  with no user apps running: the greeter's gnome-shell (UID 605xx) was 
OOM-killed and restarted
  roughly every 1.7 h (06:09, 07:50, 11:12, 12:53, 02:18 ...). So no app 
redrawing in the
  background is needed; the DP-1 hotplug flapping while DPMS is off seems to be 
the trigger.
  The problem started right after mutter was updated to 50.1-0ubuntu2.4 on 
2026-10-08.
  MUTTER_DEBUG_DISABLE_HW_CURSORS=1 removes the "Cursor update failed: 
drmModeAtomicCommit"
  spam but does NOT stop the leak.

* I will now test with mutter 50.1-0ubuntu2.2 and report back (needs an
overnight idle test).

 Apps running when the leak happened on 2026-10-10: Claude Code (CLI) in
ptyxis, VS Code, Google Chrome (~10 tabs) — all native Wayland, all idle
while the screen was locked. The same apps were open this morning
(2026-10-13): screen locked ~2 h, DP-1 still flapped ~500 times/h, but
Shmem stayed at 1–4 GB with no OOM, so the leak is intermittent. The
leak also continued in the GDM greeter with no user apps running at all,
so I don't think an app redrawing in the background is required.

** Attachment added: "log.zip"
   
https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/2170511/+attachment/6008610/+files/log.zip

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https://bugs.launchpad.net/bugs/2170511

Title:
  Shmem leak (~25 GB/h) leading to OOM when a DisplayPort monitor
  repeatedly hotplugs while DPMS is off (regression in 50.1-0ubuntu2.4)

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