Changing DPI of login screen (Ubuntu 16.04)

Question

Is it possible to change the DPI of the greeter? I have a new laptop with a 1080p screen and all of the fonts/menus are too small. I can change the scaling setting for my user account but there doesn't seem to be a way to change the scaling globally or for the greeter.

First of all, every response I've read says to edit /etc/lightdm/lightdm.conf which does not exist. The folder /etc/lightdm/lightdm.conf.d/ does exist but is empty. I have tried e.g. creating a file in that folder '50-unity-greeter.conf' with the lines:

[greeter]
xft-dpi=132

but there is no effect. I have also tried installing lightdm-gtk-greeter-settings which does have a DPI setting, but this forces my greeter into a drop-down menu mode which I do not like (I want to keep the default Unity greeter).

Any suggestions?

Thanks.

Answer 1

I found a 'good enough' solution here:

http://ubuntuhandbook.org/index.php/2014/04/ubuntu-14-04-change-login-screen-background-remove-the-white-dots/

You have to login to dconf-editor as the 'lightdm' user and edit the unity-greeter settings. The commands are:

sudo xhost +SI:localuser:lightdm
sudo su lightdm -s /bin/bash
dconf-editor

Then navigate to com > canonical > unity-greeter and change the 'xft-dpi' setting to the right value (for my 1080p screen, I set it to 132). Then reboot or restart lightdm:

sudo service lightdm restart

It's not perfect. The size of the boxes around the usernames, and the spacing between the username and the password form, do not seem to adjust to match (as they do on the lock screen after I log in). But it's much more readable.