The current login screen in Ubuntu Gnome Shell Remix is very ugly...
How can I setup another appearance for the login sreen ?
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I presume you are using Gnome 3.
You can get a screen like Ubuntu by installing the ubuntu-artwork package.
Type in terminal:
To install a custom background/theme type the following command, again in Terminal:
In the last command, replace "YOUR_FILE.JPG" with the picture you want to use as the background of the login screen.
Please note that you must specify a file which user "gdm" has permission to read, that's why I've used file:///usr/share/backgrounds/. For instance, user "gdm" cannot read files in your home directory.
In the same way you can install GTK+ Themes:
Where "THEME_NAME" is the name of the theme, e.g.: "Zukitwo". The themes must be placed under /usr/share/themes/.