Usage and customisation - Displaying a user prompt on the GNOME login screen - 《Fedora Quick Docs》

To show a user prompt on the GNOME login screen, open a terminal and perform the following steps:

Create a file for the GNOME Display Manager (GDM) configuration.

$ sudo mkdir /etc/dconf/db/gdm.d

$ vim /etc/dconf/db/gdm.d/01-hide-users

In a text editor of your choice, vim in this example, insert the following content to the /etc/dconf/db/gdm.d/01-hide-users file:
```
[org/gnome/login-screen]
banner-message-enable=true
banner-message-text='ENTER ANY MESSAGE YOU WANT HERE. FOR A NEW LINE USE \n.'
disable-restart-buttons=true
disable-user-list=true
```
To not display the banner message, do not include the first and second line. To enable the Restart button, do not include the fourth line.

Save the file and return to the terminal.
Create another file for GDM configuration.
```
$ sudo vim /etc/dconf/profile/gdm
```
Insert the following content in the /etc/dconf/profile/gdm file:
```
user-db:user
system-db:gdm
```
Save the file.
Enter the following command:
```
$ sudo dconf update
```
Check if the command was executed correctly:
```
$ ls /etc/dconf/db
```
The output should contain the following:
```
gdm gdm.d ... [output truncated]
```
Restart GDM for the changes to take effect.
```
$ sudo systemctl restart gdm
```

Displaying a user prompt on the GNOME login screen