@joshontech: as far as I know, the thing is that if lightdm-gtk-greeter is installed, you are unable to change it to another greeter (which is helpful, since if you don't have a greeter, you won't be able to make it to a GUI session)
As a workaround, I suggest you to uninstall lightdm-gtk-greeter (only if you are not using it), restart the PC and then you will see the changes applied
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Sam-Burgos commented on 2017-04-16 23:12
A couple of things related to this package:
If you upgraded from version 1.2.1 to 1.2.2, check the /etc/lightdm.conf and replace the "slick-greeter" to "lightdm-slick-greeter" in line "greeter-session" (should be line 110 if not close to that line) since the change was not done automatically, newer installations shouldn't have that problem but I will check out; this should fix the issue of not loading the greeter while starting, you might have to do this via a terminal session (CTRL+ALT+F1-F6), after that, it should work as intended. My apologies on this particular issue
This is a fork of the unity-greeter on Ubuntu (lightdm-unity-greeter as it appears here on AUR) and many options on the PKGBUILD were copied and tested as much as possible from there, if you think that there is a different or better option for compiling, you can email me with some options and I will consider them before copying here.
Don't forget to manually make the change on the lightdm.conf file to use this greeter in case the installation doesn't make the change automatically (the name of the executable in the xsession folder it's called "lightdm-slick-greeter" with no quotes). You can check the LightDM article here on the wiki for more information
Although a fork of it, this package has nothing to do with the lightdm-unity-greeter, so please don't request to make this package a conflicting one with that (unity-greeter on AUR relies on a patched version of lightdm as well, which conflicts with the original lightdm), also I suggest you not to compile this package with the patched lightdm-ubuntu since I cannot guarantee that it may work