I am using ubuntu 20.04 LTS been a year. Yesterday I wanted to change the color of the top bar. I tried to install ‘dconf-editor’ but I had got some error and the installation failed, so I uninstalled it. Then I tried to use these two commands to install gnome-tweak:
gnome-shell-extension-autohidetopbar
gnome-tweak-tool
I installed them successfully, but when I restarted, The familiar purple login screen does not appear.
I tried use ctrl+alt+f2 to enter the command interface, and then I uninstalled them, but it still not working, so I tried reinstalled gdm3, still not working, I even reinstalled the nvidia graphics driver, still not working. The problem has become more serious. I can't even use ctrl+alt+f2 to enter the command interface. I need select "Advanced options for Ubuntu" on the grub menu, and then ctrl+alt+f2 will work.
The current situation is that if I start the computer directly, it will appear on a black screen. It obviously looks like the graphics scrren (screen is black but purple), and then there is no response anymore. If I enter ‘Advanced options for Ubuntu’ in grub menu first, the ‘ctrl+alt+f2’ method is works, now I can see a blinking cursor (high resolution, obviously a graphical interface cursor, not a text cursor), and then the computer will not responsed.
How can I fix my Ubuntu? Which log file should I have to check? I have installed many software and configuration there, and my firefox’s favorites not backup, I really don’t want reinstall entire system, so will my Ubuntu survive?
