I recently tried changing the background purple color of the gnome login screen. After following primarily this guide: How do I change login screen theme or background in Ubuntu 20.04?
I changed the hex color in the ubuntu.css file, specifically in the option that contained: "loginDialog". I rebooted the system and when it booted back up instead of a login screen I was greeted with first a mouse cursor that blinked for a few seconds and then a quickly blinking underscore at the top left of the screen.
I read it is an issue with gdm, so I tried adding the nomodeset parameter as some guides suggested, reinstalling gnome, which I did multiple times, removing the sleep parameter and other various solutions. Out of desperation I installed lightdm which worked, but I wanted the ubuntu desktop so I uninstalled it.
I mostly performed various command by pressing ctrl+alt+f3 and entering what I found out is called a "ttl session"? I tried entering startx, which worked, but I now have no bottom bar and no icons on my desktop.
attached video will hopefully give you more information.
Thanks in advance.
https://streamable.com/actx52
p.s. It seems I use ubuntu 20.04 LTS.