I have verified your hypothesis regarding the device ID and the libmtp
conflict. The data confirms this is indeed a duplicate of bug #2137691,
caused by the MediaTek Bluetooth controller sharing an ID with legacy
hardware.

1. EVIDENCE FROM MY SYSTEM:
- The device is present on the USB bus with the suspect ID:
  $ lsusb -d 0489:e111
  Bus 003 Device 005: ID 0489:e111 Foxconn / Hon Hai Wireless_Device

- The conflicting MTP libraries are active:
  $ apt list --installed | grep libmtp
  libmtp-runtime/questing,now 1.1.22-1 amd64 [installed,automatic]

- The device is being detected as a USB device during boot (despite the card 
being a PCIe combo card):
  $ sudo dmesg | grep -i "0489"
  [    1.995870] usb 3-2.3: New USB device found, idVendor=0489, idProduct=e111

2. CORRELATION:
This confirms the root cause: The existing hwdb rules (specifically 
69-libmtp.hwdb) are incorrectly identifying this modern Bluetooth chip as a 
legacy "Lenovo IdeaTab" or "Medion LifeTab" (ID_MEDIA_PLAYER=1).
The segfault in bluetoothd during session handoff and resume is almost 
certainly caused by libmtp attempting to mount/probe the Bluetooth controller 
as a storage device, causing the driver to crash.

3. PROPOSED FIX (Local Override):
Since I need to retain camera functionality (I cannot simply purge libmtp), I 
propose applying a local hwdb override to untag this specific device.

Could you confirm if the following rule is the correct approach to solve
this safely until the upstream package is patched?

File: /etc/udev/hwdb.d/99-fix-bluetooth.hwdb
------------------------------------------------
# Force disable MTP and GPhoto2 for MediaTek Bluetooth Chip (0489:e111)
usb:v0489pE111*
 ID_MEDIA_PLAYER=0
 ID_MTP_DEVICE=0
 ID_GPHOTO2=0
 GPHOTO2_DRIVER=none
------------------------------------------------

If confirmed, I will apply this, run `systemd-hwdb update` and `udevadm
trigger`, and report back if it resolves the crash.

** Tags added: mt7925e

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https://bugs.launchpad.net/bugs/2137719

Title:
  bluetoothd 5.83 segfault during GDM to Desktop session handoff on
  Ubuntu 25.10 (MediaTek MT7925 / GNOME 49)

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