error messages after removing a usb drive

I removed a WD Passport USB drive last night from my laptop and got the following from syslog1 this morning (after getting the error message):

May 11 22:32:36 D830 gvfs-udisks2-vo[1700]: gvfs_udisks2_drive_stop_finish: assertion 'g_async_result_is_tagged (result, gvfs_udisks2_drive_stop)' failed
May 11 22:32:36 D830 gvfs-udisks2-vo[1700]: g_dbus_method_invocation_return_gerror: assertion 'error != NULL' failed
May 11 22:32:36 D830 gvfs-udisks2-vo[1700]: g_error_free: assertion 'error != NULL' failed
May 11 22:32:36 D830 upowerd[1821]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:1.0
May 11 22:32:36 D830 upowerd[1821]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:1d.7/usb2/2-1

Appears to be a failure of gvfs.

Please see https://ubuntu-mate.community/t/um-18-04-error-message-after-safely-removing-drive/16742