Comment 27 for bug 1430561

I was able to duplicate this bug on Ubuntu 18.14 while installing HPLIP for Laserjet Pro MFP M125mW
During the scanner plugin install I get the same error.

When I installed separately the sudo apt install libcanberra-gtk-module

Then i got the following error

HP Linux Imaging and Printing System (ver. 3.18.12)
Plugin Installer ver. 3.0

Copyright (c) 2001-15 HP Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

Plug-in version: 3.18.12
Installed HPLIP version: 3.18.12
Number of files to install: 55

Plugin installation failed
error: Python gobject/dbus may be not installed
error: Plug-in install failed.

There is a very simple workaround to fix this.

Just go to HP website directly and download your hplip plugin.
In my case it was hplip-3.18.12-plugin.run
HP website address is https://developers.hp.com/hp-linux-imaging-and-printing/plugins
Download the plugin to Documents folder
Then open terminal, go to Documents folder and install the plugin with command sh hplip-3.18.12-plugin.run and follow instructions on the screen.

This should fix your HP Scanner problem.