The Sony "earplugs" WF-1000XM3 are two devices that should somehow pair as a
single device.
With Linux it does not work correctly for reasons unknown.
It means I see the device connected, but I can't select it as audio output
device.
One effect are repeating syslog messages like this:
kernel: Bluetooth: hci0: advertising data len corrected

Using hcidump I get messages like this:
> HCI Event: LE Meta Event (0x3e) plen 42
    LE Advertising Report
      ADV_IND - Connectable undirected advertising (0)
      bdaddr 94:DB:56:12:34:56 (Public)
      Unknown type 0x16 with 5 bytes data
      TX power level: 244
      Complete service classes: 0xfe03
      Complete local name: 'LE_WF-1000XM3'
      RSSI: -49
> HCI Event: LE Meta Event (0x3e) plen 35
    LE Advertising Report
      SCAN_RSP - Scan Response (4)
      bdaddr 94:DB:56:12:34:56 (Public)
      Unknown type 0xff with 21 bytes data
      RSSI: -49
> HCI Event: LE Meta Event (0x3e) plen 42
    LE Advertising Report
      ADV_IND - Connectable undirected advertising (0)
      bdaddr 94:DB:56:12:34:56 (Public)
      Unknown type 0x16 with 5 bytes data
      TX power level: 244
      Complete service classes: 0xfe03
      Complete local name: 'LE_WF-1000XM3'
      RSSI: -49

Trying a manual pair via bluetoothctl, I can scan, pair, and connect.
Seems the bluetooth stack is not ready for BT 5.0 devices, or the device is
somewhat non-standard.