Ubuntu 1710 Daily Builds LightDM Session
The Unity Greeter is powered by LightDM

Ubuntu is switching to GDM as the default display manager in both Ubuntu 17.10 and 18.04 LTS.

With GNOME Shell now installed on and running as the default desktop in Ubuntu 17.10 daily builds, decisions on other details are starting to fall into place.

One of them being the topic of which display manager to use to power the login screen.

And a decision has been reached: Ubuntu 17.10 will use GDM (GNOME Display Manager) by default, replacing LightDM.

Ubuntu switched to LightDM in Ubuntu 11.10.

GDM will appear in the main Ubuntu archives shortly, after which it’ll likely be added to the various meta packages that make up the default Ubuntu desktop experience and trickle down to be installed by default in the daily builds.

This all takes time, so don’t expect to boot up and see it quite yet.

Ubuntu Will Use GDM

“We’ve attempted to get the GNOME Shell lock screen running with LightDM and using GNOME Shell as a LightDM Greeter. Which this still seems possible, it’s not easy to patch GNOME Shell as the GDM code is hard to decouple,” Ancell explains.

“Given the workload we have and the risks in modifying GNOME the decision is to use GDM for 17.10 and thus 18.04 LTS.”

What will this mean for you, the user? Well, in one regards, nothing – after all, you never see LightDM either (the bit you ‘see’ is the Unity Greeter, which runs on top of LightDM).

But given that Ancell’s previous comments on Unity Greeter was “we clearly would not use it”, it’s probable that the standard GDM greeter (which I don’t believe has a specific name) will be used on Ubuntu going forward.

Hopefully with some new theming!

So, in that case, the decision that means an all-new login screen and new lock screen.

GDM isn’t a whole lot different to use. You’;; still be able to switch between different desktop sessions (presumably including Unity 7, should you re-install it), plus access some additional features, like music controls on the lock-screen when music is playing.

One feature you won’t find is guest sessions .As it stands today GDM does not support guest sessions. But, to be fair, Ubuntu doesn’t either — not any more. Last month Ubuntu pushed out an update that disables guest sessions in LightDM on Ubuntu due to a security flaw that could allow guest session users to access the contents of other users’ home folders.

LightDM Support ‘Limited to Bug Fixes’

Ancell adds that Ubuntu will ‘continue to support LightDM for the supported Ubuntu releases’ (14.04 LTS, 16.04 LTS and 17.04) and ‘for use in the other flavours’.

Although this “support” will ‘be limited to bug fixes from the Ubuntu desktop team’, this is open-source and anyone can get involved to contribute fixes, patches and features.

Are you happy to see Ubuntu adopt the upstream GNOME display manager? Or will you be reverting to LightDM as soon as you can?

gdm lightdm login ubuntu 17.10